Reducing the overhead of timestamps in positioning state information (PSI) reports

ABSTRACT

Disclosed are techniques for wireless communication. In an aspect, a user equipment (UE) performs at least one positioning measurement of at least one downlink positioning reference signal (DL-PRS) received from a transmission-reception point (TRP) during a positioning session, reports, to a positioning entity, a value of the at least one positioning measurement via low layer signaling, and determines a timestamp for the at least one positioning measurement relative to a reference point, wherein the timestamp comprises an amount of time between the reference point and a time at which the at least one positioning measurement is valid.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present Application for Patent claims the benefit of U.S.Provisional Application No. 63/025,622, entitled “REDUCING THE OVERHEADOF TIMESTAMPS IN POSITIONING STATE INFORMATION (PSI) REPORTS,” filed May15, 2020, assigned to the assignee hereof, and expressly incorporatedherein by reference in its entirety.

BACKGROUND OF THE DISCLOSURE 1. Field of the Disclosure

Aspects of the disclosure relate generally to wireless communications.

2. Description of the Related Art

Wireless communication systems have developed through variousgenerations, including a first-generation analog wireless phone service(1G), a second-generation (2G) digital wireless phone service (includinginterim 2.5G and 2.75G networks), a third-generation (3G) high speeddata, Internet-capable wireless service and a fourth-generation (4G)service (e.g., Long Term Evolution (LTE) or WiMax). There are presentlymany different types of wireless communication systems in use, includingcellular and personal communications service (PCS) systems. Examples ofknown cellular systems include the cellular analog advanced mobile phonesystem (AMPS), and digital cellular systems based on code divisionmultiple access (CDMA), frequency division multiple access (FDMA), timedivision multiple access (TDMA), the Global System for Mobilecommunications (GSM), etc.

A fifth generation (5G) wireless standard, referred to as New Radio(NR), calls for higher data transfer speeds, greater numbers ofconnections, and better coverage, among other improvements. The 5Gstandard, according to the Next Generation Mobile Networks Alliance, isdesigned to provide data rates of several tens of megabits per second toeach of tens of thousands of users, with 1 gigabit per second to tens ofworkers on an office floor. Several hundreds of thousands ofsimultaneous connections should be supported in order to support largesensor deployments. Consequently, the spectral efficiency of 5G mobilecommunications should be significantly enhanced compared to the current4G standard. Furthermore, signaling efficiencies should be enhanced andlatency should be substantially reduced compared to current standards.

SUMMARY

The following presents a simplified summary relating to one or moreaspects disclosed herein. Thus, the following summary should not beconsidered an extensive overview relating to all contemplated aspects,nor should the following summary be considered to identify key orcritical elements relating to all contemplated aspects or to delineatethe scope associated with any particular aspect. Accordingly, thefollowing summary has the sole purpose to present certain conceptsrelating to one or more aspects relating to the mechanisms disclosedherein in a simplified form to precede the detailed descriptionpresented below.

In an aspect, a method of wireless communication performed by a userequipment (UE) includes performing at least one positioning measurementof at least one downlink positioning reference signal (DL-PRS) receivedfrom a transmission-reception point (TRP) during a positioning session;reporting, to a positioning entity, a value of the at least onepositioning measurement via low layer signaling; and determining atimestamp for the at least one positioning measurement relative to areference point, wherein the timestamp comprises an amount of timerelative to the reference point that the at least one positioningmeasurement is valid.

In an aspect, a method of wireless communication performed by a networkentity includes receiving, from a user equipment (UE) via low layersignaling, a value of at least one positioning measurement of at leastone downlink positioning reference signal (DL-PRS), the value of the atleast one positioning measurement received at a reception time during apositioning session between the network entity and the UE; determining areference point for a timestamp for the at least one positioningmeasurement; and determining the timestamp based on the reception time,the reference point, and an offset, wherein the timestamp comprises anamount of time relative to the reference point that the at least onepositioning measurement is valid.

In an aspect, a user equipment (UE) includes a memory; at least onetransceiver; and at least one processor communicatively coupled to thememory and the at least one transceiver, the at least one processorconfigured to: perform at least one positioning measurement of at leastone downlink positioning reference signal (DL-PRS) received from atransmission-reception point (TRP) during a positioning session; report,to a positioning entity, a value of the at least one positioningmeasurement via low layer signaling; and determine a timestamp for theat least one positioning measurement relative to a reference point,wherein the timestamp comprises an amount of time relative to thereference point that the at least one positioning measurement is valid.

In an aspect, a network entity includes a memory; at least onetransceiver; and at least one processor communicatively coupled to thememory and the at least one transceiver, the at least one processorconfigured to: receive, via the at least one transceiver, from a userequipment (UE) via low layer signaling, a value of at least onepositioning measurement of at least one downlink positioning referencesignal (DL-PRS), the value of the at least one positioning measurementreceived at a reception time during a positioning session between thenetwork entity and the UE; determine a reference point for a timestampfor the at least one positioning measurement; and determine thetimestamp based on the reception time, the reference point, and anoffset, wherein the timestamp comprises an amount of time relative tothe reference point that the at least one positioning measurement isvalid.

In an aspect, a user equipment (UE) includes means for performing atleast one positioning measurement of at least one downlink positioningreference signal (DL-PRS) received from a transmission-reception point(TRP) during a positioning session; means for reporting, to apositioning entity, a value of the at least one positioning measurementvia low layer signaling; and means for determining a timestamp for theat least one positioning measurement relative to a reference point,wherein the timestamp comprises an amount of time relative to thereference point that the at least one positioning measurement is valid.

In an aspect, a network entity includes means for receiving, from a userequipment (UE) via low layer signaling, a value of at least onepositioning measurement of at least one downlink positioning referencesignal (DL-PRS), the value of the at least one positioning measurementreceived at a reception time during a positioning session between thenetwork entity and the UE; means for determining a reference point for atimestamp for the at least one positioning measurement; and means fordetermining the timestamp based on the reception time, the referencepoint, and an offset, wherein the timestamp comprises an amount of timerelative to the reference point that the at least one positioningmeasurement is valid.

In an aspect, a non-transitory computer-readable medium storescomputer-executable instructions that, when executed by a user equipment(UE), cause the UE to: perform at least one positioning measurement ofat least one downlink positioning reference signal (DL-PRS) receivedfrom a transmission-reception point (TRP) during a positioning session;report, to a positioning entity, a value of the at least one positioningmeasurement via low layer signaling; and determine a timestamp for theat least one positioning measurement relative to a reference point,wherein the timestamp comprises an amount of time relative to thereference point that the at least one positioning measurement is valid.

In an aspect, a non-transitory computer-readable medium storescomputer-executable instructions that, when executed by a networkentity, cause the network entity to: receive, from a user equipment (UE)via low layer signaling, a value of at least one positioning measurementof at least one downlink positioning reference signal (DL-PRS), thevalue of the at least one positioning measurement received at areception time during a positioning session between the network entityand the UE; determine a reference point for a timestamp for the at leastone positioning measurement; and determine the timestamp based on thereception time, the reference point, and an offset, wherein thetimestamp comprises an amount of time relative to the reference pointthat the at least one positioning measurement is valid.

Other objects and advantages associated with the aspects disclosedherein will be apparent to those skilled in the art based on theaccompanying drawings and detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are presented to aid in the description ofvarious aspects of the disclosure and are provided solely forillustration of the aspects and not limitation thereof.

FIG. 1 illustrates an example wireless communications system, accordingto aspects of the disclosure.

FIGS. 2A and 2B illustrate example wireless network structures,according to aspects of the disclosure.

FIGS. 3A, 3B, and 3C are simplified block diagrams of several sampleaspects of components that may be employed in a user equipment (UE), abase station, and a network entity, respectively, and configured tosupport communications as taught herein.

FIGS. 4A to 4D are diagrams illustrating example frame structures andchannels within the frame structures, according to aspects of thedisclosure.

FIG. 5 illustrates an example wireless network structure showinghigh-layer architecture enhancements for low-latency positioning.

FIGS. 6A to 6C illustrate various LTE positioning protocol (LPP)information elements (IEs) that a UE can use to report positioningmeasurements to a location server.

FIG. 7 illustrates another IE a UE can use to report positioningmeasurements to a location server.

FIG. 8 illustrates a timeline in which positioning reference signals(PRS) are transmitted inside time chunks within some length of time.

FIGS. 9 and 10 illustrate example methods of wireless communication,according to aspects of the disclosure.

DETAILED DESCRIPTION

Aspects of the disclosure are provided in the following description andrelated drawings directed to various examples provided for illustrationpurposes. Alternate aspects may be devised without departing from thescope of the disclosure. Additionally, well-known elements of thedisclosure will not be described in detail or will be omitted so as notto obscure the relevant details of the disclosure.

The words “exemplary” and/or “example” are used herein to mean “servingas an example, instance, or illustration.” Any aspect described hereinas “exemplary” and/or “example” is not necessarily to be construed aspreferred or advantageous over other aspects. Likewise, the term“aspects of the disclosure” does not require that all aspects of thedisclosure include the discussed feature, advantage or mode ofoperation.

Those of skill in the art will appreciate that the information andsignals described below may be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that may bereferenced throughout the description below may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof, depending inpart on the particular application, in part on the desired design, inpart on the corresponding technology, etc.

Further, many aspects are described in terms of sequences of actions tobe performed by, for example, elements of a computing device. It will berecognized that various actions described herein can be performed byspecific circuits (e.g., application specific integrated circuits(ASICs)), by program instructions being executed by one or moreprocessors, or by a combination of both. Additionally, the sequence(s)of actions described herein can be considered to be embodied entirelywithin any form of non-transitory computer-readable storage mediumhaving stored therein a corresponding set of computer instructions that,upon execution, would cause or instruct an associated processor of adevice to perform the functionality described herein. Thus, the variousaspects of the disclosure may be embodied in a number of differentforms, all of which have been contemplated to be within the scope of theclaimed subject matter. In addition, for each of the aspects describedherein, the corresponding form of any such aspects may be describedherein as, for example, “logic configured to” perform the describedaction.

As used herein, the terms “user equipment” (UE) and “base station” arenot intended to be specific or otherwise limited to any particular radioaccess technology (RAT), unless otherwise noted. In general, a UE may beany wireless communication device (e.g., a mobile phone, router, tabletcomputer, laptop computer, consumer asset locating device, wearable(e.g., smartwatch, glasses, augmented reality (AR)/virtual reality (VR)headset, etc.), vehicle (e.g., automobile, motorcycle, bicycle, etc.),Internet of Things (IoT) device, etc.) used by a user to communicateover a wireless communications network. A UE may be mobile or may (e.g.,at certain times) be stationary, and may communicate with a radio accessnetwork (RAN). As used herein, the term “UE” may be referred tointerchangeably as an “access terminal” or “AT,” a “client device,” a“wireless device,” a “subscriber device,” a “subscriber terminal,” a“subscriber station,” a “user terminal” or “UT,” a “mobile device,” a“mobile terminal,” a “mobile station,” or variations thereof. Generally,UEs can communicate with a core network via a RAN, and through the corenetwork the UEs can be connected with external networks such as theInternet and with other UEs. Of course, other mechanisms of connectingto the core network and/or the Internet are also possible for the UEs,such as over wired access networks, wireless local area network (WLAN)networks (e.g., based on the Institute of Electrical and ElectronicsEngineers (IEEE) 802.11 specification, etc.) and so on.

A base station may operate according to one of several RATs incommunication with UEs depending on the network in which it is deployed,and may be alternatively referred to as an access point (AP), a networknode, a NodeB, an evolved NodeB (eNB), a next generation eNB (ng-eNB), aNew Radio (NR) Node B (also referred to as a gNB or gNodeB), etc. A basestation may be used primarily to support wireless access by UEs,including supporting data, voice, and/or signaling connections for thesupported UEs. In some systems a base station may provide purely edgenode signaling functions while in other systems it may provideadditional control and/or network management functions. A communicationlink through which UEs can send signals to a base station is called anuplink (UL) channel (e.g., a reverse traffic channel, a reverse controlchannel, an access channel, etc.). A communication link through whichthe base station can send signals to UEs is called a downlink (DL) orforward link channel (e.g., a paging channel, a control channel, abroadcast channel, a forward traffic channel, etc.). As used herein theterm traffic channel (TCH) can refer to either an uplink/reverse ordownlink/forward traffic channel.

The term “base station” may refer to a single physicaltransmission-reception point (TRP) or to multiple physical TRPs that mayor may not be co-located. For example, where the term “base station”refers to a single physical TRP, the physical TRP may be an antenna ofthe base station corresponding to a cell (or several cell sectors) ofthe base station. Where the term “base station” refers to multipleco-located physical TRPs, the physical TRPs may be an array of antennas(e.g., as in a multiple-input multiple-output (MIMO) system or where thebase station employs beamforming) of the base station. Where the term“base station” refers to multiple non-co-located physical TRPs, thephysical TRPs may be a distributed antenna system (DAS) (a network ofspatially separated antennas connected to a common source via atransport medium) or a remote radio head (RRH) (a remote base stationconnected to a serving base station). Alternatively, the non-co-locatedphysical TRPs may be the serving base station receiving the measurementreport from the UE and a neighbor base station whose reference radiofrequency (RF) signals the UE is measuring. Because a TRP is the pointfrom which a base station transmits and receives wireless signals, asused herein, references to transmission from or reception at a basestation are to be understood as referring to a particular TRP of thebase station.

In some implementations that support positioning of UEs, a base stationmay not support wireless access by UEs (e.g., may not support data,voice, and/or signaling connections for UEs), but may instead transmitreference signals to UEs to be measured by the UEs, and/or may receiveand measure signals transmitted by the UEs. Such a base station may bereferred to as a positioning beacon (e.g., when transmitting signals toUEs) and/or as a location measurement unit (e.g., when receiving andmeasuring signals from UEs).

An “RF signal” comprises an electromagnetic wave of a given frequencythat transports information through the space between a transmitter anda receiver. As used herein, a transmitter may transmit a single “RFsignal” or multiple “RF signals” to a receiver. However, the receivermay receive multiple “RF signals” corresponding to each transmitted RFsignal due to the propagation characteristics of RF signals throughmultipath channels. The same transmitted RF signal on different pathsbetween the transmitter and receiver may be referred to as a “multipath”RF signal. As used herein, an RF signal may also be referred to as a“wireless signal” or simply a “signal” where it is clear from thecontext that the term “signal” refers to a wireless signal or an RFsignal.

FIG. 1 illustrates an example wireless communications system 100,according to aspects of the disclosure. The wireless communicationssystem 100 (which may also be referred to as a wireless wide areanetwork (WWAN)) may include various base stations 102 (labeled “BS”) andvarious UEs 104. The base stations 102 may include macro cell basestations (high power cellular base stations) and/or small cell basestations (low power cellular base stations). In an aspect, the macrocell base stations may include eNBs and/or ng-eNBs where the wirelesscommunications system 100 corresponds to an LTE network, or gNBs wherethe wireless communications system 100 corresponds to a NR network, or acombination of both, and the small cell base stations may includefemtocells, picocells, microcells, etc.

The base stations 102 may collectively form a RAN and interface with acore network 170 (e.g., an evolved packet core (EPC) or a 5G core (5GC))through backhaul links 122, and through the core network 170 to one ormore location servers 172 (e.g., a location management function (LMF) ora secure user plane location (SUPL) location platform (SLP)). Thelocation server(s) 172 may be part of core network 170 or may beexternal to core network 170. In addition to other functions, the basestations 102 may perform functions that relate to one or more oftransferring user data, radio channel ciphering and deciphering,integrity protection, header compression, mobility control functions(e.g., handover, dual connectivity), inter-cell interferencecoordination, connection setup and release, load balancing, distributionfor non-access stratum (NAS) messages, NAS node selection,synchronization, RAN sharing, multimedia broadcast multicast service(MBMS), subscriber and equipment trace, RAN information management(RIM), paging, positioning, and delivery of warning messages. The basestations 102 may communicate with each other directly or indirectly(e.g., through the EPC/5GC) over backhaul links 134, which may be wiredor wireless.

The base stations 102 may wirelessly communicate with the UEs 104. Eachof the base stations 102 may provide communication coverage for arespective geographic coverage area 110. In an aspect, one or more cellsmay be supported by a base station 102 in each geographic coverage area110. A “cell” is a logical communication entity used for communicationwith a base station (e.g., over some frequency resource, referred to asa carrier frequency, component carrier, carrier, band, or the like), andmay be associated with an identifier (e.g., a physical cell identifier(PCI), an enhanced cell identifier (ECI), a virtual cell identifier(VCI), a cell global identifier (CGI), etc.) for distinguishing cellsoperating via the same or a different carrier frequency. In some cases,different cells may be configured according to different protocol types(e.g., machine-type communication (MTC), narrowband IoT (NB-IoT),enhanced mobile broadband (eMBB), or others) that may provide access fordifferent types of UEs. Because a cell is supported by a specific basestation, the term “cell” may refer to either or both of the logicalcommunication entity and the base station that supports it, depending onthe context. In addition, because a TRP is typically the physicaltransmission point of a cell, the terms “cell” and “TRP” may be usedinterchangeably. In some cases, the term “cell” may also refer to ageographic coverage area of a base station (e.g., a sector), insofar asa carrier frequency can be detected and used for communication withinsome portion of geographic coverage areas 110.

While neighboring macro cell base station 102 geographic coverage areas110 may partially overlap (e.g., in a handover region), some of thegeographic coverage areas 110 may be substantially overlapped by alarger geographic coverage area 110. For example, a small cell basestation 102′ (labeled “SC” for “small cell”) may have a geographiccoverage area 110′ that substantially overlaps with the geographiccoverage area 110 of one or more macro cell base stations 102. A networkthat includes both small cell and macro cell base stations may be knownas a heterogeneous network. A heterogeneous network may also includehome eNBs (HeNBs), which may provide service to a restricted group knownas a closed subscriber group (CSG).

The communication links 120 between the base stations 102 and the UEs104 may include uplink (also referred to as reverse link) transmissionsfrom a UE 104 to a base station 102 and/or downlink (DL) (also referredto as forward link) transmissions from a base station 102 to a UE 104.The communication links 120 may use MIMO antenna technology, includingspatial multiplexing, beamforming, and/or transmit diversity. Thecommunication links 120 may be through one or more carrier frequencies.Allocation of carriers may be asymmetric with respect to downlink anduplink (e.g., more or less carriers may be allocated for downlink thanfor uplink).

The wireless communications system 100 may further include a wirelesslocal area network (WLAN) access point (AP) 150 in communication withWLAN stations (STAs) 152 via communication links 154 in an unlicensedfrequency spectrum (e.g., 5 GHz). When communicating in an unlicensedfrequency spectrum, the WLAN STAs 152 and/or the WLAN AP 150 may performa clear channel assessment (CCA) or listen before talk (LBT) procedureprior to communicating in order to determine whether the channel isavailable.

The small cell base station 102′ may operate in a licensed and/or anunlicensed frequency spectrum. When operating in an unlicensed frequencyspectrum, the small cell base station 102′ may employ LTE or NRtechnology and use the same 5 GHz unlicensed frequency spectrum as usedby the WLAN AP 150. The small cell base station 102′, employing LTE/5Gin an unlicensed frequency spectrum, may boost coverage to and/orincrease capacity of the access network. NR in unlicensed spectrum maybe referred to as NR-U. LTE in an unlicensed spectrum may be referred toas LTE-U, licensed assisted access (LAA), or MulteFire.

The wireless communications system 100 may further include a millimeterwave (mmW) base station 180 that may operate in mmW frequencies and/ornear mmW frequencies in communication with a UE 182. Extremely highfrequency (EHF) is part of the RF in the electromagnetic spectrum. EHFhas a range of 30 GHz to 300 GHz and a wavelength between 1 millimeterand 10 millimeters. Radio waves in this band may be referred to as amillimeter wave. Near mmW may extend down to a frequency of 3 GHz with awavelength of 100 millimeters. The super high frequency (SHF) bandextends between 3 GHz and 30 GHz, also referred to as centimeter wave.Communications using the mmW/near mmW radio frequency band have highpath loss and a relatively short range. The mmW base station 180 and theUE 182 may utilize beamforming (transmit and/or receive) over a mmWcommunication link 184 to compensate for the extremely high path lossand short range. Further, it will be appreciated that in alternativeconfigurations, one or more base stations 102 may also transmit usingmmW or near mmW and beamforming. Accordingly, it will be appreciatedthat the foregoing illustrations are merely examples and should not beconstrued to limit the various aspects disclosed herein.

Transmit beamforming is a technique for focusing an RF signal in aspecific direction. Traditionally, when a network node (e.g., a basestation) broadcasts an RF signal, it broadcasts the signal in alldirections (omni-directionally). With transmit beamforming, the networknode determines where a given target device (e.g., a UE) is located(relative to the transmitting network node) and projects a strongerdownlink RF signal in that specific direction, thereby providing afaster (in terms of data rate) and stronger RF signal for the receivingdevice(s). To change the directionality of the RF signal whentransmitting, a network node can control the phase and relativeamplitude of the RF signal at each of the one or more transmitters thatare broadcasting the RF signal. For example, a network node may use anarray of antennas (referred to as a “phased array” or an “antennaarray”) that creates a beam of RF waves that can be “steered” to pointin different directions, without actually moving the antennas.Specifically, the RF current from the transmitter is fed to theindividual antennas with the correct phase relationship so that theradio waves from the separate antennas add together to increase theradiation in a desired direction, while cancelling to suppress radiationin undesired directions.

Transmit beams may be quasi-co-located, meaning that they appear to thereceiver (e.g., a UE) as having the same parameters, regardless ofwhether or not the transmitting antennas of the network node themselvesare physically co-located. In NR, there are four types ofquasi-co-location (QCL) relations. Specifically, a QCL relation of agiven type means that certain parameters about a second reference RFsignal on a second beam can be derived from information about a sourcereference RF signal on a source beam. Thus, if the source reference RFsignal is QCL Type A, the receiver can use the source reference RFsignal to estimate the Doppler shift, Doppler spread, average delay, anddelay spread of a second reference RF signal transmitted on the samechannel. If the source reference RF signal is QCL Type B, the receivercan use the source reference RF signal to estimate the Doppler shift andDoppler spread of a second reference RF signal transmitted on the samechannel. If the source reference RF signal is QCL Type C, the receivercan use the source reference RF signal to estimate the Doppler shift andaverage delay of a second reference RF signal transmitted on the samechannel. If the source reference RF signal is QCL Type D, the receivercan use the source reference RF signal to estimate the spatial receiveparameter of a second reference RF signal transmitted on the samechannel.

In receive beamforming, the receiver uses a receive beam to amplify RFsignals detected on a given channel. For example, the receiver canincrease the gain setting and/or adjust the phase setting of an array ofantennas in a particular direction to amplify (e.g., to increase thegain level of) the RF signals received from that direction. Thus, when areceiver is said to beamform in a certain direction, it means the beamgain in that direction is high relative to the beam gain along otherdirections, or the beam gain in that direction is the highest comparedto the beam gain in that direction of all other receive beams availableto the receiver. This results in a stronger received signal strength(e.g., reference signal received power (RSRP), reference signal receivedquality (RSRQ), signal-to-interference-plus-noise ratio (SINR), etc.) ofthe RF signals received from that direction.

Transmit and receive beams may be spatially related. A spatial relationmeans that parameters for a second beam (e.g., a transmit or receivebeam) for a second reference signal can be derived from informationabout a first beam (e.g., a receive beam or a transmit beam) for a firstreference signal. For example, a UE may use a particular receive beam toreceive a reference downlink reference signal (e.g., synchronizationsignal block (SSB)) from a base station. The UE can then form a transmitbeam for sending an uplink reference signal (e.g., sounding referencesignal (SRS)) to that base station based on the parameters of thereceive beam.

Note that a “downlink” beam may be either a transmit beam or a receivebeam, depending on the entity forming it. For example, if a base stationis forming the downlink beam to transmit a reference signal to a UE, thedownlink beam is a transmit beam. If the UE is forming the downlinkbeam, however, it is a receive beam to receive the downlink referencesignal. Similarly, an “uplink” beam may be either a transmit beam or areceive beam, depending on the entity forming it. For example, if a basestation is forming the uplink beam, it is an uplink receive beam, and ifa UE is forming the uplink beam, it is an uplink transmit beam.

In 5G, the frequency spectrum in which wireless nodes (e.g., basestations 102/180, UEs 104/182) operate is divided into multiplefrequency ranges, FR1 (from 450 to 6000 MHz), FR2 (from 24250 to 52600MHz), FR3 (above 52600 MHz), and FR4 (between FR1 and FR2). mmWfrequency bands generally include the FR2, FR3, and FR4 frequencyranges. As such, the terms “mmW” and “FR2” or “FR3” or “FR4” maygenerally be used interchangeably.

In a multi-carrier system, such as 5G, one of the carrier frequencies isreferred to as the “primary carrier” or “anchor carrier” or “primaryserving cell” or “PCell,” and the remaining carrier frequencies arereferred to as “secondary carriers” or “secondary serving cells” or“SCells.” In carrier aggregation, the anchor carrier is the carrieroperating on the primary frequency (e.g., FR1) utilized by a UE 104/182and the cell in which the UE 104/182 either performs the initial radioresource control (RRC) connection establishment procedure or initiatesthe RRC connection re-establishment procedure. The primary carriercarries all common and UE-specific control channels, and may be acarrier in a licensed frequency (however, this is not always the case).A secondary carrier is a carrier operating on a second frequency (e.g.,FR2) that may be configured once the RRC connection is establishedbetween the UE 104 and the anchor carrier and that may be used toprovide additional radio resources. In some cases, the secondary carriermay be a carrier in an unlicensed frequency. The secondary carrier maycontain only necessary signaling information and signals, for example,those that are UE-specific may not be present in the secondary carrier,since both primary uplink and downlink carriers are typicallyUE-specific. This means that different UEs 104/182 in a cell may havedifferent downlink primary carriers. The same is true for the uplinkprimary carriers. The network is able to change the primary carrier ofany UE 104/182 at any time. This is done, for example, to balance theload on different carriers. Because a “serving cell” (whether a PCell oran SCell) corresponds to a carrier frequency/component carrier overwhich some base station is communicating, the term “cell,” “servingcell,” “component carrier,” “carrier frequency,” and the like can beused interchangeably.

For example, still referring to FIG. 1 , one of the frequencies utilizedby the macro cell base stations 102 may be an anchor carrier (or“PCell”) and other frequencies utilized by the macro cell base stations102 and/or the mmW base station 180 may be secondary carriers(“SCells”). The simultaneous transmission and/or reception of multiplecarriers enables the UE 104/182 to significantly increase its datatransmission and/or reception rates. For example, two 20 MHz aggregatedcarriers in a multi-carrier system would theoretically lead to atwo-fold increase in data rate (i.e., 40 MHz), compared to that attainedby a single 20 MHz carrier.

The wireless communications system 100 may further include a UE 164 thatmay communicate with a macro cell base station 102 over a communicationlink 120 and/or the mmW base station 180 over a mmW communication link184. For example, the macro cell base station 102 may support a PCelland one or more SCells for the UE 164 and the mmW base station 180 maysupport one or more SCells for the UE 164.

In the example of FIG. 1 , one or more Earth orbiting satellitepositioning system (SPS) space vehicles (SVs) 112 (e.g., satellites) maybe used as an independent source of location information for any of theillustrated UEs (shown in FIG. 1 as a single UE 104 for simplicity). AUE 104 may include one or more dedicated SPS receivers specificallydesigned to receive SPS signals 124 for deriving geo locationinformation from the SVs 112. An SPS typically includes a system oftransmitters (e.g., SVs 112) positioned to enable receivers (e.g., UEs104) to determine their location on or above the Earth based, at leastin part, on signals (e.g., SPS signals 124) received from thetransmitters. Such a transmitter typically transmits a signal markedwith a repeating pseudo-random noise (PN) code of a set number of chips.While typically located in SVs 112, transmitters may sometimes belocated on ground-based control stations, base stations 102, and/orother UEs 104.

The use of SPS signals 124 can be augmented by various satellite-basedaugmentation systems (SBAS) that may be associated with or otherwiseenabled for use with one or more global and/or regional navigationsatellite systems. For example an SBAS may include an augmentationsystem(s) that provides integrity information, differential corrections,etc., such as the Wide Area Augmentation System (WAAS), the EuropeanGeostationary Navigation Overlay Service (EGNOS), the Multi-functionalSatellite Augmentation System (MSAS), the Global Positioning System(GPS) Aided Geo Augmented Navigation or GPS and Geo Augmented Navigationsystem (GAGAN), and/or the like. Thus, as used herein, an SPS mayinclude any combination of one or more global and/or regional navigationsatellite systems and/or augmentation systems, and SPS signals 124 mayinclude SPS, SPS-like, and/or other signals associated with such one ormore SPS.

The wireless communications system 100 may further include one or moreUEs, such as UE 190, that connects indirectly to one or morecommunication networks via one or more device-to-device (D2D)peer-to-peer (P2P) links (referred to as “sidelinks”). In the example ofFIG. 1 , UE 190 has a D2D P2P link 192 with one of the UEs 104 connectedto one of the base stations 102 (e.g., through which UE 190 mayindirectly obtain cellular connectivity) and a D2D P2P link 194 withWLAN STA 152 connected to the WLAN AP 150 (through which UE 190 mayindirectly obtain WLAN-based Internet connectivity). In an example, theD2D P2P links 192 and 194 may be supported with any well-known D2D RAT,such as LTE Direct (LTE-D), WiFi Direct (WiFi-D), Bluetooth®, and so on.

FIG. 2A illustrates an example wireless network structure 200. Forexample, a 5GC 210 (also referred to as a Next Generation Core (NGC))can be viewed functionally as control plane (C-plane) functions 214(e.g., UE registration, authentication, network access, gatewayselection, etc.) and user plane (U-plane) functions 212, (e.g., UEgateway function, access to data networks, IP routing, etc.) whichoperate cooperatively to form the core network. User plane interface(NG-U) 213 and control plane interface (NG-C) 215 connect the gNB 222 tothe 5GC 210 and specifically to the user plane functions 212 and controlplane functions 214, respectively. In an additional configuration, anng-eNB 224 may also be connected to the 5GC 210 via NG-C 215 to thecontrol plane functions 214 and NG-U 213 to user plane functions 212.Further, ng-eNB 224 may directly communicate with gNB 222 via a backhaulconnection 223. In some configurations, a Next Generation RAN (NG-RAN)220 may have one or more gNBs 222, while other configurations includeone or more of both ng-eNBs 224 and gNBs 222. Either (or both) gNB 222or ng-eNB 224 may communicate with one or more UEs 204 (e.g., any of theUEs described herein).

Another optional aspect may include a location server 230, which may bein communication with the 5GC 210 to provide location assistance forUE(s) 204. The location server 230 can be implemented as a plurality ofseparate servers (e.g., physically separate servers, different softwaremodules on a single server, different software modules spread acrossmultiple physical servers, etc.), or alternately may each correspond toa single server. The location server 230 can be configured to supportone or more location services for UEs 204 that can connect to thelocation server 230 via the core network, 5GC 210, and/or via theInternet (not illustrated). Further, the location server 230 may beintegrated into a component of the core network, or alternatively may beexternal to the core network (e.g., a third party server, such as anoriginal equipment manufacturer (OEM) server or service server).

FIG. 2B illustrates another example wireless network structure 250. A5GC 260 (which may correspond to 5GC 210 in FIG. 2A) can be viewedfunctionally as control plane functions, provided by an access andmobility management function (AMF) 264, and user plane functions,provided by a user plane function (UPF) 262, which operate cooperativelyto form the core network (i.e., 5GC 260). The functions of the AMF 264include registration management, connection management, reachabilitymanagement, mobility management, lawful interception, transport forsession management (SM) messages between one or more UEs 204 (e.g., anyof the UEs described herein) and a session management function (SMF)266, transparent proxy services for routing SM messages, accessauthentication and access authorization, transport for short messageservice (SMS) messages between the UE 204 and the short message servicefunction (SMSF) (not shown), and security anchor functionality (SEAF).The AMF 264 also interacts with an authentication server function (AUSF)(not shown) and the UE 204, and receives the intermediate key that wasestablished as a result of the UE 204 authentication process. In thecase of authentication based on a UMTS (universal mobiletelecommunications system) subscriber identity module (USIM), the AMF264 retrieves the security material from the AUSF. The functions of theAMF 264 also include security context management (SCM). The SCM receivesa key from the SEAF that it uses to derive access-network specific keys.The functionality of the AMF 264 also includes location servicesmanagement for regulatory services, transport for location servicesmessages between the UE 204 and a location management function (LMF) 270(which acts as a location server 230), transport for location servicesmessages between the NG-RAN 220 and the LMF 270, evolved packet system(EPS) bearer identifier allocation for interworking with the EPS, and UE204 mobility event notification. In addition, the AMF 264 also supportsfunctionalities for non-3GPP (Third Generation Partnership Project)access networks.

Functions of the UPF 262 include acting as an anchor point forintra-/inter-RAT mobility (when applicable), acting as an externalprotocol data unit (PDU) session point of interconnect to a data network(not shown), providing packet routing and forwarding, packet inspection,user plane policy rule enforcement (e.g., gating, redirection, trafficsteering), lawful interception (user plane collection), traffic usagereporting, quality of service (QoS) handling for the user plane (e.g.,uplink/downlink rate enforcement, reflective QoS marking in thedownlink), uplink traffic verification (service data flow (SDF) to QoSflow mapping), transport level packet marking in the uplink anddownlink, downlink packet buffering and downlink data notificationtriggering, and sending and forwarding of one or more “end markers” tothe source RAN node. The UPF 262 may also support transfer of locationservices messages over a user plane between the UE 204 and a locationserver, such as an SLP 272.

The functions of the SMF 266 include session management, UE Internetprotocol (IP) address allocation and management, selection and controlof user plane functions, configuration of traffic steering at the UPF262 to route traffic to the proper destination, control of part ofpolicy enforcement and QoS, and downlink data notification. Theinterface over which the SMF 266 communicates with the AMF 264 isreferred to as the N11 interface.

Another optional aspect may include an LMF 270, which may be incommunication with the 5GC 260 to provide location assistance for UEs204. The LMF 270 can be implemented as a plurality of separate servers(e.g., physically separate servers, different software modules on asingle server, different software modules spread across multiplephysical servers, etc.), or alternately may each correspond to a singleserver. The LMF 270 can be configured to support one or more locationservices for UEs 204 that can connect to the LMF 270 via the corenetwork, 5GC 260, and/or via the Internet (not illustrated). The SLP 272may support similar functions to the LMF 270, but whereas the LMF 270may communicate with the AMF 264, NG-RAN 220, and UEs 204 over a controlplane (e.g., using interfaces and protocols intended to convey signalingmessages and not voice or data), the SLP 272 may communicate with UEs204 and external clients (not shown in FIG. 2B) over a user plane (e.g.,using protocols intended to carry voice and/or data like thetransmission control protocol (TCP) and/or IP).

User plane interface 263 and control plane interface 265 connect the 5GC260, and specifically the UPF 262 and AMF 264, respectively, to one ormore gNBs 222 and/or ng-eNBs 224 in the NG-RAN 220. The interfacebetween gNB(s) 222 and/or ng-eNB(s) 224 and the AMF 264 is referred toas the “N2” interface, and the interface between gNB(s) 222 and/orng-eNB(s) 224 and the UPF 262 is referred to as the “N3” interface. ThegNB(s) 222 and/or ng-eNB(s) 224 of the NG-RAN 220 may communicatedirectly with each other via backhaul connections 223, referred to asthe “Xn-C” interface. One or more of gNBs 222 and/or ng-eNBs 224 maycommunicate with one or more UEs 204 over a wireless interface, referredto as the “Uu” interface.

The functionality of a gNB 222 is divided between a gNB central unit(gNB-CU) 226 and one or more gNB distributed units (gNB-DUs) 228. Theinterface 232 between the gNB-CU 226 and the one or more gNB-DUs 228 isreferred to as the “F1” interface. A gNB-CU 226 is a logical node thatincludes the base station functions of transferring user data, mobilitycontrol, radio access network sharing, positioning, session management,and the like, except for those functions allocated exclusively to thegNB-DU(s) 228. More specifically, the gNB-CU 226 hosts the radioresource control (RRC), service data adaptation protocol (SDAP), andpacket data convergence protocol (PDCP) protocols of the gNB 222. AgNB-DU 228 is a logical node that hosts the radio link control (RLC),medium access control (MAC), and physical (PHY) layers of the gNB 222.Its operation is controlled by the gNB-CU 226. One gNB-DU 228 cansupport one or more cells, and one cell is supported by only one gNB-DU228. Thus, a UE 204 communicates with the gNB-CU 226 via the RRC, SDAP,and PDCP layers and with a gNB-DU 228 via the RLC, MAC, and PHY layers.

FIGS. 3A, 3B, and 3C illustrate several example components (representedby corresponding blocks) that may be incorporated into a UE 302 (whichmay correspond to any of the UEs described herein), a base station 304(which may correspond to any of the base stations described herein), anda network entity 306 (which may correspond to or embody any of thenetwork functions described herein, including the location server 230and the LMF 270, or alternatively may be independent from the NG-RAN 220and/or 5GC 210/260 infrastructure depicted in FIGS. 2A and 2B, such as aprivate network) to support the file transmission operations as taughtherein. It will be appreciated that these components may be implementedin different types of apparatuses in different implementations (e.g., inan ASIC, in a system-on-chip (SoC), etc.). The illustrated componentsmay also be incorporated into other apparatuses in a communicationsystem. For example, other apparatuses in a system may includecomponents similar to those described to provide similar functionality.Also, a given apparatus may contain one or more of the components. Forexample, an apparatus may include multiple transceiver components thatenable the apparatus to operate on multiple carriers and/or communicatevia different technologies.

The UE 302 and the base station 304 each include one or more wirelesswide area network (WWAN) transceivers 310 and 350, respectively,providing means for communicating (e.g., means for transmitting, meansfor receiving, means for measuring, means for tuning, means forrefraining from transmitting, etc.) via one or more wirelesscommunication networks (not shown), such as an NR network, an LTEnetwork, a GSM network, and/or the like. The WWAN transceivers 310 and350 may each be connected to one or more antennas 316 and 356,respectively, for communicating with other network nodes, such as otherUEs, access points, base stations (e.g., eNBs, gNBs), etc., via at leastone designated RAT (e.g., NR, LTE, GSM, etc.) over a wirelesscommunication medium of interest (e.g., some set of time/frequencyresources in a particular frequency spectrum). The WWAN transceivers 310and 350 may be variously configured for transmitting and encodingsignals 318 and 358 (e.g., messages, indications, information, and soon), respectively, and, conversely, for receiving and decoding signals318 and 358 (e.g., messages, indications, information, pilots, and soon), respectively, in accordance with the designated RAT. Specifically,the WWAN transceivers 310 and 350 include one or more transmitters 314and 354, respectively, for transmitting and encoding signals 318 and358, respectively, and one or more receivers 312 and 352, respectively,for receiving and decoding signals 318 and 358, respectively.

The UE 302 and the base station 304 each also include, at least in somecases, one or more short-range wireless transceivers 320 and 360,respectively. The short-range wireless transceivers 320 and 360 may beconnected to one or more antennas 326 and 366, respectively, and providemeans for communicating (e.g., means for transmitting, means forreceiving, means for measuring, means for tuning, means for refrainingfrom transmitting, etc.) with other network nodes, such as other UEs,access points, base stations, etc., via at least one designated RAT(e.g., WiFi, LTE-D, Bluetooth®, Zigbee®, Z-Wave®, PC5, dedicatedshort-range communications (DSRC), wireless access for vehicularenvironments (WAVE), near-field communication (NFC), etc.) over awireless communication medium of interest. The short-range wirelesstransceivers 320 and 360 may be variously configured for transmittingand encoding signals 328 and 368 (e.g., messages, indications,information, and so on), respectively, and, conversely, for receivingand decoding signals 328 and 368 (e.g., messages, indications,information, pilots, and so on), respectively, in accordance with thedesignated RAT. Specifically, the short-range wireless transceivers 320and 360 include one or more transmitters 324 and 364, respectively, fortransmitting and encoding signals 328 and 368, respectively, and one ormore receivers 322 and 362, respectively, for receiving and decodingsignals 328 and 368, respectively. As specific examples, the short-rangewireless transceivers 320 and 360 may be WiFi transceivers, Bluetooth®transceivers, Zigbee® and/or Z-Wave® transceivers, NFC transceivers, orvehicle-to-vehicle (V2V) and/or vehicle-to-everything (V2X)transceivers.

The UE 302 and the base station 304 also include, at least in somecases, satellite positioning systems (SPS) receivers 330 and 370. TheSPS receivers 330 and 370 may be connected to one or more antennas 336and 376, respectively, and may provide means for receiving and/ormeasuring SPS signals 338 and 378, respectively, such as globalpositioning system (GPS) signals, global navigation satellite system(GLONASS) signals, Galileo signals, Beidou signals, Indian RegionalNavigation Satellite System (NAVIC), Quasi-Zenith Satellite System(QZSS), etc. The SPS receivers 330 and 370 may comprise any suitablehardware and/or software for receiving and processing SPS signals 338and 378, respectively. The SPS receivers 330 and 370 request informationand operations as appropriate from the other systems, and performscalculations necessary to determine positions of the UE 302 and the basestation 304 using measurements obtained by any suitable SPS algorithm.

The base station 304 and the network entity 306 each include one or morenetwork transceivers 380 and 390, respectively, providing means forcommunicating (e.g., means for transmitting, means for receiving, etc.)with other network entities (e.g., other base stations 304, othernetwork entities 306). For example, the base station 304 may employ theone or more network transceivers 380 to communicate with other basestations 304 or network entities 306 over one or more wired or wirelessbackhaul links. As another example, the network entity 306 may employthe one or more network transceivers 390 to communicate with one or morebase station 304 over one or more wired or wireless backhaul links, orwith other network entities 306 over one or more wired or wireless corenetwork interfaces.

A transceiver may be configured to communicate over a wired or wirelesslink. A transceiver (whether a wired transceiver or a wirelesstransceiver) includes transmitter circuitry (e.g., transmitters 314,324, 354, 364) and receiver circuitry (e.g., receivers 312, 322, 352,362). A transceiver may be an integrated device (e.g., embodyingtransmitter circuitry and receiver circuitry in a single device) in someimplementations, may comprise separate transmitter circuitry andseparate receiver circuitry in some implementations, or may be embodiedin other ways in other implementations. The transmitter circuitry andreceiver circuitry of a wired transceiver (e.g., network transceivers380 and 390 in some implementations) may be coupled to one or more wirednetwork interface ports. Wireless transmitter circuitry (e.g.,transmitters 314, 324, 354, 364) may include or be coupled to aplurality of antennas (e.g., antennas 316, 326, 356, 366), such as anantenna array, that permits the respective apparatus (e.g., UE 302, basestation 304) to perform transmit “beamforming,” as described herein.Similarly, wireless receiver circuitry (e.g., receivers 312, 322, 352,362) may include or be coupled to a plurality of antennas (e.g.,antennas 316, 326, 356, 366), such as an antenna array, that permits therespective apparatus (e.g., UE 302, base station 304) to perform receivebeamforming, as described herein. In an aspect, the transmittercircuitry and receiver circuitry may share the same plurality ofantennas (e.g., antennas 316, 326, 356, 366), such that the respectiveapparatus can only receive or transmit at a given time, not both at thesame time. A wireless transceiver (e.g., WWAN transceivers 310 and 350,short-range wireless transceivers 320 and 360) may also include anetwork listen module (NLM) or the like for performing variousmeasurements.

As used herein, the various wireless transceivers (e.g., transceivers310, 320, 350, and 360, and network transceivers 380 and 390 in someimplementations) and wired transceivers (e.g., network transceivers 380and 390 in some implementations) may generally be characterized as “atransceiver,” “at least one transceiver,” or “one or more transceivers.”As such, whether a particular transceiver is a wired or wirelesstransceiver may be inferred from the type of communication performed.For example, backhaul communication between network devices or serverswill generally relate to signaling via a wired transceiver, whereaswireless communication between a UE (e.g., UE 302) and a base station(e.g., base station 304) will generally relate to signaling via awireless transceiver.

The UE 302, the base station 304, and the network entity 306 alsoinclude other components that may be used in conjunction with theoperations as disclosed herein. The UE 302, the base station 304, andthe network entity 306 include one or more processors 332, 384, and 394,respectively, for providing functionality relating to, for example,wireless communication, and for providing other processingfunctionality. The processors 332, 384, and 394 may therefore providemeans for processing, such as means for determining, means forcalculating, means for receiving, means for transmitting, means forindicating, etc. In an aspect, the processors 332, 384, and 394 mayinclude, for example, one or more general purpose processors, multi-coreprocessors, central processing units (CPUs), ASICs, digital signalprocessors (DSPs), field programmable gate arrays (FPGAs), otherprogrammable logic devices or processing circuitry, or variouscombinations thereof.

The UE 302, the base station 304, and the network entity 306 includememory circuitry implementing memories 340, 386, and 396 (e.g., eachincluding a memory device), respectively, for maintaining information(e.g., information indicative of reserved resources, thresholds,parameters, and so on). The memories 340, 386, and 396 may thereforeprovide means for storing, means for retrieving, means for maintaining,etc. In some cases, the UE 302, the base station 304, and the networkentity 306 may include positioning component 342, 388, and 398,respectively. The positioning component 342, 388, and 398 may behardware circuits that are part of or coupled to the processors 332,384, and 394, respectively, that, when executed, cause the UE 302, thebase station 304, and the network entity 306 to perform thefunctionality described herein. In other aspects, the positioningcomponent 342, 388, and 398 may be external to the processors 332, 384,and 394 (e.g., part of a modem processing system, integrated withanother processing system, etc.). Alternatively, the positioningcomponent 342, 388, and 398 may be memory modules stored in the memories340, 386, and 396, respectively, that, when executed by the processors332, 384, and 394 (or a modem processing system, another processingsystem, etc.), cause the UE 302, the base station 304, and the networkentity 306 to perform the functionality described herein. FIG. 3Aillustrates possible locations of the positioning component 342, whichmay be, for example, part of the one or more WWAN transceivers 310, thememory 340, the one or more processors 332, or any combination thereof,or may be a standalone component. FIG. 3B illustrates possible locationsof the positioning component 388, which may be, for example, part of theone or more WWAN transceivers 350, the memory 386, the one or moreprocessors 384, or any combination thereof, or may be a standalonecomponent. FIG. 3C illustrates possible locations of the positioningcomponent 398, which may be, for example, part of the one or morenetwork transceivers 390, the memory 396, the one or more processors394, or any combination thereof, or may be a standalone component.

The UE 302 may include one or more sensors 344 coupled to the one ormore processors 332 to provide means for sensing or detecting movementand/or orientation information that is independent of motion dataderived from signals received by the one or more WWAN transceivers 310,the one or more short-range wireless transceivers 320, and/or the SPSreceiver 330. By way of example, the sensor(s) 344 may include anaccelerometer (e.g., a micro-electrical mechanical systems (MEMS)device), a gyroscope, a geomagnetic sensor (e.g., a compass), analtimeter (e.g., a barometric pressure altimeter), and/or any other typeof movement detection sensor. Moreover, the sensor(s) 344 may include aplurality of different types of devices and combine their outputs inorder to provide motion information. For example, the sensor(s) 344 mayuse a combination of a multi-axis accelerometer and orientation sensorsto provide the ability to compute positions in two-dimensional (2D)and/or three-dimensional (3D) coordinate systems.

In addition, the UE 302 includes a user interface 346 providing meansfor providing indications (e.g., audible and/or visual indications) to auser and/or for receiving user input (e.g., upon user actuation of asensing device such a keypad, a touch screen, a microphone, and so on).Although not shown, the base station 304 and the network entity 306 mayalso include user interfaces.

Referring to the one or more processors 384 in more detail, in thedownlink, IP packets from the network entity 306 may be provided to theprocessor 384. The one or more processors 384 may implementfunctionality for an RRC layer, a packet data convergence protocol(PDCP) layer, a radio link control (RLC) layer, and a medium accesscontrol (MAC) layer. The one or more processors 384 may provide RRClayer functionality associated with broadcasting of system information(e.g., master information block (MIB), system information blocks(SIBs)), RRC connection control (e.g., RRC connection paging, RRCconnection establishment, RRC connection modification, and RRCconnection release), inter-RAT mobility, and measurement configurationfor UE measurement reporting; PDCP layer functionality associated withheader compression/decompression, security (ciphering, deciphering,integrity protection, integrity verification), and handover supportfunctions; RLC layer functionality associated with the transfer of upperlayer PDUs, error correction through automatic repeat request (ARQ),concatenation, segmentation, and reassembly of RLC service data units(SDUs), re-segmentation of RLC data PDUs, and reordering of RLC dataPDUs; and MAC layer functionality associated with mapping betweenlogical channels and transport channels, scheduling informationreporting, error correction, priority handling, and logical channelprioritization.

The transmitter 354 and the receiver 352 may implement Layer-1 (L1)functionality associated with various signal processing functions.Layer-1, which includes a physical (PHY) layer, may include errordetection on the transport channels, forward error correction (FEC)coding/decoding of the transport channels, interleaving, rate matching,mapping onto physical channels, modulation/demodulation of physicalchannels, and MIMO antenna processing. The transmitter 354 handlesmapping to signal constellations based on various modulation schemes(e.g., binary phase-shift keying (BPSK), quadrature phase-shift keying(QPSK), M-phase-shift keying (M-PSK), M-quadrature amplitude modulation(M-QAM)). The coded and modulated symbols may then be split intoparallel streams. Each stream may then be mapped to an orthogonalfrequency division multiplexing (OFDM) subcarrier, multiplexed with areference signal (e.g., pilot) in the time and/or frequency domain, andthen combined together using an inverse fast Fourier transform (IFFT) toproduce a physical channel carrying a time domain OFDM symbol stream.The OFDM symbol stream is spatially precoded to produce multiple spatialstreams. Channel estimates from a channel estimator may be used todetermine the coding and modulation scheme, as well as for spatialprocessing. The channel estimate may be derived from a reference signaland/or channel condition feedback transmitted by the UE 302. Eachspatial stream may then be provided to one or more different antennas356. The transmitter 354 may modulate an RF carrier with a respectivespatial stream for transmission.

At the UE 302, the receiver 312 receives a signal through its respectiveantenna(s) 316. The receiver 312 recovers information modulated onto anRF carrier and provides the information to the one or more processors332. The transmitter 314 and the receiver 312 implement Layer-1functionality associated with various signal processing functions. Thereceiver 312 may perform spatial processing on the information torecover any spatial streams destined for the UE 302. If multiple spatialstreams are destined for the UE 302, they may be combined by thereceiver 312 into a single OFDM symbol stream. The receiver 312 thenconverts the OFDM symbol stream from the time-domain to the frequencydomain using a fast Fourier transform (FFT). The frequency domain signalcomprises a separate OFDM symbol stream for each subcarrier of the OFDMsignal. The symbols on each subcarrier, and the reference signal, arerecovered and demodulated by determining the most likely signalconstellation points transmitted by the base station 304. These softdecisions may be based on channel estimates computed by a channelestimator. The soft decisions are then decoded and de-interleaved torecover the data and control signals that were originally transmitted bythe base station 304 on the physical channel. The data and controlsignals are then provided to the one or more processors 332, whichimplements Layer-3 (L3) and Layer-2 (L2) functionality.

In the uplink, the one or more processors 332 provides demultiplexingbetween transport and logical channels, packet reassembly, deciphering,header decompression, and control signal processing to recover IPpackets from the core network. The one or more processors 332 are alsoresponsible for error detection.

Similar to the functionality described in connection with the downlinktransmission by the base station 304, the one or more processors 332provides RRC layer functionality associated with system information(e.g., MIB, SIBs) acquisition, RRC connections, and measurementreporting; PDCP layer functionality associated with headercompression/decompression, and security (ciphering, deciphering,integrity protection, integrity verification); RLC layer functionalityassociated with the transfer of upper layer PDUs, error correctionthrough ARQ, concatenation, segmentation, and reassembly of RLC SDUs,re-segmentation of RLC data PDUs, and reordering of RLC data PDUs; andMAC layer functionality associated with mapping between logical channelsand transport channels, multiplexing of MAC SDUs onto transport blocks(TBs), demultiplexing of MAC SDUs from TBs, scheduling informationreporting, error correction through hybrid automatic repeat request(HARD), priority handling, and logical channel prioritization.

Channel estimates derived by the channel estimator from a referencesignal or feedback transmitted by the base station 304 may be used bythe transmitter 314 to select the appropriate coding and modulationschemes, and to facilitate spatial processing. The spatial streamsgenerated by the transmitter 314 may be provided to different antenna(s)316. The transmitter 314 may modulate an RF carrier with a respectivespatial stream for transmission.

The uplink transmission is processed at the base station 304 in a mannersimilar to that described in connection with the receiver function atthe UE 302. The receiver 352 receives a signal through its respectiveantenna(s) 356. The receiver 352 recovers information modulated onto anRF carrier and provides the information to the one or more processors384.

In the uplink, the one or more processors 384 provides demultiplexingbetween transport and logical channels, packet reassembly, deciphering,header decompression, control signal processing to recover IP packetsfrom the UE 302. IP packets from the one or more processors 384 may beprovided to the core network. The one or more processors 384 are alsoresponsible for error detection.

For convenience, the UE 302, the base station 304, and/or the networkentity 306 are shown in FIGS. 3A, 3B, and 3C as including variouscomponents that may be configured according to the various examplesdescribed herein. It will be appreciated, however, that the illustratedcomponents may have different functionality in different designs. Inparticular, various components in FIGS. 3A to 3C are optional inalternative configurations and the various aspects includeconfigurations that may vary due to design choice, costs, use of thedevice, or other considerations. For example, in case of FIG. 3A, aparticular implementation of UE 302 may omit the WWAN transceiver(s) 310(e.g., a wearable device or tablet computer or PC or laptop may haveWi-Fi and/or Bluetooth capability without cellular capability), or mayomit the short-range wireless transceiver(s) 320 (e.g., cellular-only,etc.), or may omit the SPS receiver 330, or may omit the sensor(s) 344,and so on. In another example, in case of FIG. 3B, a particularimplementation of the base station 304 may omit the WWAN transceiver(s)350 (e.g., a Wi-Fi “hotspot” access point without cellular capability),or may omit the short-range wireless transceiver(s) 360 (e.g.,cellular-only, etc.), or may omit the SPS receiver 370, and so on. Forbrevity, illustration of the various alternative configurations is notprovided herein, but would be readily understandable to one skilled inthe art.

The various components of the UE 302, the base station 304, and thenetwork entity 306 may communicate with each other over data buses 334,382, and 392, respectively. In an aspect, the data buses 334, 382, and392 may form, or be part of, a communication interface of the UE 302,the base station 304, and the network entity 306, respectively. Forexample, where different logical entities are embodied in the samedevice (e.g., gNB and location server functionality incorporated intothe same base station 304), the data buses 334, 382, and 392 may providecommunication between them.

The components of FIGS. 3A, 3B, and 3C may be implemented in variousways. In some implementations, the components of FIGS. 3A, 3B, and 3Cmay be implemented in one or more circuits such as, for example, one ormore processors and/or one or more ASICs (which may include one or moreprocessors). Here, each circuit may use and/or incorporate at least onememory component for storing information or executable code used by thecircuit to provide this functionality. For example, some or all of thefunctionality represented by blocks 310 to 346 may be implemented byprocessor and memory component(s) of the UE 302 (e.g., by execution ofappropriate code and/or by appropriate configuration of processorcomponents). Similarly, some or all of the functionality represented byblocks 350 to 388 may be implemented by processor and memorycomponent(s) of the base station 304 (e.g., by execution of appropriatecode and/or by appropriate configuration of processor components). Also,some or all of the functionality represented by blocks 390 to 398 may beimplemented by processor and memory component(s) of the network entity306 (e.g., by execution of appropriate code and/or by appropriateconfiguration of processor components). For simplicity, variousoperations, acts, and/or functions are described herein as beingperformed “by a UE,” “by a base station,” “by a network entity,” etc.However, as will be appreciated, such operations, acts, and/or functionsmay actually be performed by specific components or combinations ofcomponents of the UE 302, base station 304, network entity 306, etc.,such as the processors 332, 384, 394, the transceivers 310, 320, 350,and 360, the memories 340, 386, and 396, the positioning component 342,388, and 398, etc.

In some designs, the network entity 306 may be implemented as a corenetwork component. In other designs, the network entity 306 may bedistinct from a network operator or operation of the cellular networkinfrastructure (e.g., NG RAN 220 and/or 5GC 210/260). For example, thenetwork entity 306 may be a component of a private network that may beconfigured to communicate with the UE 302 via the base station 304 orindependently from the base station 304 (e.g., over a non-cellularcommunication link, such as WiFi).

Various frame structures may be used to support downlink and uplinktransmissions between network nodes (e.g., base stations and UEs). FIG.4A is a diagram 400 illustrating an example of a downlink framestructure, according to aspects of the disclosure. FIG. 4B is a diagram430 illustrating an example of channels within the downlink framestructure, according to aspects of the disclosure. FIG. 4C is a diagram450 illustrating an example of an uplink frame structure, according toaspects of the disclosure. FIG. 4D is a diagram 480 illustrating anexample of channels within an uplink frame structure, according toaspects of the disclosure. Other wireless communications technologiesmay have different frame structures and/or different channels.

LTE, and in some cases NR, utilizes OFDM on the downlink andsingle-carrier frequency division multiplexing (SC-FDM) on the uplink.Unlike LTE, however, NR has an option to use OFDM on the uplink as well.OFDM and SC-FDM partition the system bandwidth into multiple (K)orthogonal subcarriers, which are also commonly referred to as tones,bins, etc. Each subcarrier may be modulated with data. In general,modulation symbols are sent in the frequency domain with OFDM and in thetime domain with SC-FDM. The spacing between adjacent subcarriers may befixed, and the total number of subcarriers (K) may be dependent on thesystem bandwidth. For example, the spacing of the subcarriers may be 15kilohertz (kHz) and the minimum resource allocation (resource block) maybe 12 subcarriers (or 180 kHz). Consequently, the nominal FFT size maybe equal to 128, 256, 512, 1024, or 2048 for system bandwidth of 1.25,2.5, 5, 10, or 20 megahertz (MHz), respectively. The system bandwidthmay also be partitioned into subbands. For example, a subband may cover1.08 MHz (i.e., 6 resource blocks), and there may be 1, 2, 4, 8, or 16subbands for system bandwidth of 1.25, 2.5, 5, 10, or 20 MHz,respectively.

LTE supports a single numerology (subcarrier spacing (SCS), symbollength, etc.). In contrast, NR may support multiple numerologies (μ),for example, subcarrier spacings of 15 kHz (μ=0), 30 kHz (μ=1), 60 kHz(μ=2), 120 kHz (μ=3), and 240 kHz (μ=4) or greater may be available. Ineach subcarrier spacing, there are 14 symbols per slot. For 15 kHz SCS(μ=0), there is one slot per subframe, 10 slots per frame, the slotduration is 1 millisecond (ms), the symbol duration is 66.7 microseconds(μs), and the maximum nominal system bandwidth (in MHz) with a 4K FFTsize is 50. For 30 kHz SCS (μ=1), there are two slots per subframe, 20slots per frame, the slot duration is 0.5 milliseconds (ms), the symbolduration is 33.3 μs, and the maximum nominal system bandwidth (in MHz)with a 4K FFT size is 100. For 60 kHz SCS (μ=2), there are four slotsper subframe, 40 slots per frame, the slot duration is 0.25 ms, thesymbol duration is 16.7 μs, and the maximum nominal system bandwidth (inMHz) with a 4K FFT size is 200. For 120 kHz SCS (μ=3), there are eightslots per subframe, 80 slots per frame, the slot duration is 0.125 ms,the symbol duration is 8.33 μs, and the maximum nominal system bandwidth(in MHz) with a 4K FFT size is 400. For 240 kHz SCS (μ=4), there are 16slots per subframe, 160 slots per frame, the slot duration is 0.0625 ms,the symbol duration is 4.17 μs, and the maximum nominal system bandwidth(in MHz) with a 4K FFT size is 800.

In the example of FIGS. 4A to 4D, a numerology of 15 kHz is used. Thus,in the time domain, a 10 ms frame is divided into 10 equally sizedsubframes of 1 ms each, and each subframe includes one time slot. InFIGS. 4A to 4D, time is represented horizontally (on the X axis) withtime increasing from left to right, while frequency is representedvertically (on the Y axis) with frequency increasing (or decreasing)from bottom to top.

A resource grid may be used to represent time slots, each time slotincluding one or more time-concurrent resource blocks (RBs) (alsoreferred to as physical RBs (PRBs)) in the frequency domain. Theresource grid is further divided into multiple resource elements (REs).An RE may correspond to one symbol length in the time domain and onesubcarrier in the frequency domain. In the numerology of FIGS. 4A to 4D,for a normal cyclic prefix, an RB may contain 12 consecutive subcarriersin the frequency domain and seven consecutive symbols in the timedomain, for a total of 84 REs. For an extended cyclic prefix, an RB maycontain 12 consecutive subcarriers in the frequency domain and sixconsecutive symbols in the time domain, for a total of 72 REs. Thenumber of bits carried by each RE depends on the modulation scheme.

Some of the REs carry downlink reference (pilot) signals (DL-RS). TheDL-RS may include positioning reference signals (PRS), trackingreference signals (TRS), phase tracking reference signals (PTRS),cell-specific reference signals (CRS), channel state informationreference signals (CSI-RS), demodulation reference signals (DMRS),primary synchronization signals (PSS), secondary synchronization signals(SSS), synchronization signal blocks (SSBs), etc. FIG. 4A illustratesexample locations of REs carrying PRS (labeled “R”).

A collection of resource elements (REs) that are used for transmissionof PRS is referred to as a “PRS resource.” The collection of resourceelements can span multiple PRBs in the frequency domain and ‘N’ (such as1 or more) consecutive symbol(s) within a slot in the time domain. In agiven OFDM symbol in the time domain, a PRS resource occupiesconsecutive PRBs in the frequency domain.

The transmission of a PRS resource within a given PRB has a particularcomb size (also referred to as the “comb density”). A comb size ‘N’represents the subcarrier spacing (or frequency/tone spacing) withineach symbol of a PRS resource configuration. Specifically, for a combsize ‘N,’ PRS are transmitted in every Nth subcarrier of a symbol of aPRB. For example, for comb-4, for each symbol of the PRS resourceconfiguration, REs corresponding to every fourth subcarrier (such assubcarriers 0, 4, 8) are used to transmit PRS of the PRS resource.Currently, comb sizes of comb-2, comb-4, comb-6, and comb-12 aresupported for DL-PRS. FIG. 4A illustrates an example PRS resourceconfiguration for comb-6 (which spans six symbols). That is, thelocations of the shaded REs (labeled “R”) indicate a comb-6 PRS resourceconfiguration.

Currently, a DL-PRS resource may span 2, 4, 6, or 12 consecutive symbolswithin a slot with a fully frequency-domain staggered pattern. A DL-PRSresource can be configured in any higher layer configured downlink orflexible (FL) symbol of a slot. There may be a constant energy perresource element (EPRE) for all REs of a given DL-PRS resource. Thefollowing are the frequency offsets from symbol to symbol for comb sizes2, 4, 6, and 12 over 2, 4, 6, and 12 symbols. 2-symbol comb-2: {0, 1};4-symbol comb-2: {0, 1, 0, 1}; 6-symbol comb-2: {0, 1, 0, 1, 0, 1};12-symbol comb-2: {0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1}; 4-symbol comb-4:{0, 2, 1, 3}; 12-symbol comb-4: {0, 2, 1, 3, 0, 2, 1, 3, 0, 2, 1, 3};6-symbol comb-6: {0, 3, 1, 4, 2, 5}; 12-symbol comb-6: {0, 3, 1, 4, 2,5, 0, 3, 1, 4, 2, 5}; and 12-symbol comb-12: {0, 6, 3, 9, 1, 7, 4, 10,2, 8, 5, 11}.

A “PRS resource set” is a set of PRS resources used for the transmissionof PRS signals, where each PRS resource has a PRS resource ID. Inaddition, the PRS resources in a PRS resource set are associated withthe same TRP. A PRS resource set is identified by a PRS resource set IDand is associated with a particular TRP (identified by a TRP ID). Inaddition, the PRS resources in a PRS resource set have the sameperiodicity, a common muting pattern configuration, and the samerepetition factor (such as “PRS-ResourceRepetitionFactor”) across slots.The periodicity is the time from the first repetition of the first PRSresource of a first PRS instance to the same first repetition of thesame first PRS resource of the next PRS instance. The periodicity mayhave a length selected from 2{circumflex over ( )}μ, {4, 5, 8, 10, 16,20, 32, 40, 64, 80, 160, 320, 640, 1280, 2560, 5120, 10240} slots, withμ=0, 1, 2, 3. The repetition factor may have a length selected from {1,2, 4, 6, 8, 16, 32} slots.

A PRS resource ID in a PRS resource set is associated with a single beam(or beam ID) transmitted from a single TRP (where a TRP may transmit oneor more beams). That is, each PRS resource of a PRS resource set may betransmitted on a different beam, and as such, a “PRS resource,” orsimply “resource,” also can be referred to as a “beam.” Note that thisdoes not have any implications on whether the TRPs and the beams onwhich PRS are transmitted are known to the UE.

A “PRS instance” or “PRS occasion” is one instance of a periodicallyrepeated time window (such as a group of one or more consecutive slots)where PRS are expected to be transmitted. A PRS occasion also may bereferred to as a “PRS positioning occasion,” a “PRS positioninginstance, a “positioning occasion,” “a positioning instance,” a“positioning repetition,” or simply an “occasion,” an “instance,” or a“repetition.”

A “positioning frequency layer” (also referred to simply as a “frequencylayer”) is a collection of one or more PRS resource sets across one ormore TRPs that have the same values for certain parameters.Specifically, the collection of PRS resource sets has the samesubcarrier spacing and cyclic prefix (CP) type (meaning all numerologiessupported for the PDSCH are also supported for PRS), the same Point A,the same value of the downlink PRS bandwidth, the same start PRB (andcenter frequency), and the same comb-size. The Point A parameter takesthe value of the parameter “ARFCN-ValueNR” (where “ARFCN” stands for“absolute radio-frequency channel number”) and is an identifier/codethat specifies a pair of physical radio channel used for transmissionand reception. The downlink PRS bandwidth may have a granularity of fourPRBs, with a minimum of 24 PRBs and a maximum of 272 PRBs. Currently, upto four frequency layers have been defined, and up to two PRS resourcesets may be configured per TRP per frequency layer.

The concept of a frequency layer is somewhat like the concept ofcomponent carriers and bandwidth parts (BWPs), but different in thatcomponent carriers and BWPs are used by one base station (or a macrocell base station and a small cell base station) to transmit datachannels, while frequency layers are used by several (usually three ormore) base stations to transmit PRS. A UE may indicate the number offrequency layers it can support when it sends the network itspositioning capabilities, such as during an LTE positioning protocol(LPP) session. For example, a UE may indicate whether it can support oneor four positioning frequency layers.

FIG. 4B illustrates an example of various channels within a downlinkslot of a radio frame. In NR, the channel bandwidth, or systembandwidth, is divided into multiple BWPs. A BWP is a contiguous set ofPRBs selected from a contiguous subset of the common RBs for a givennumerology on a given carrier. Generally, a maximum of four BWPs can bespecified in the downlink and uplink. That is, a UE can be configuredwith up to four BWPs on the downlink, and up to four BWPs on the uplink.Only one BWP (uplink or downlink) may be active at a given time, meaningthe UE may only receive or transmit over one BWP at a time. On thedownlink, the bandwidth of each BWP should be equal to or greater thanthe bandwidth of the SSB, but it may or may not contain the SSB.

Referring to FIG. 4B, a primary synchronization signal (PSS) is used bya UE to determine subframe/symbol timing and a physical layer identity.A secondary synchronization signal (SSS) is used by a UE to determine aphysical layer cell identity group number and radio frame timing. Basedon the physical layer identity and the physical layer cell identitygroup number, the UE can determine a PCI. Based on the PCI, the UE candetermine the locations of the aforementioned DL-RS. The physicalbroadcast channel (PBCH), which carries an MIB, may be logically groupedwith the PSS and SSS to form an SSB (also referred to as an SS/PBCH).The MIB provides a number of RBs in the downlink system bandwidth and asystem frame number (SFN). The physical downlink shared channel (PDSCH)carries user data, broadcast system information not transmitted throughthe PBCH, such as system information blocks (SIBs), and paging messages.

The physical downlink control channel (PDCCH) carries downlink controlinformation (DCI) within one or more control channel elements (CCEs),each CCE including one or more RE group (REG) bundles (which may spanmultiple symbols in the time domain), each REG bundle including one ormore REGs, each REG corresponding to 12 resource elements (one resourceblock) in the frequency domain and one OFDM symbol in the time domain.The set of physical resources used to carry the PDCCH/DCI is referred toin NR as the control resource set (CORESET). In NR, a PDCCH is confinedto a single CORESET and is transmitted with its own DMRS. This enablesUE-specific beamforming for the PDCCH.

In the example of FIG. 4B, there is one CORESET per BWP, and the CORESETspans three symbols (although it may be only one or two symbols) in thetime domain. Unlike LTE control channels, which occupy the entire systembandwidth, in NR, PDCCH channels are localized to a specific region inthe frequency domain (i.e., a CORESET). Thus, the frequency component ofthe PDCCH shown in FIG. 4B is illustrated as less than a single BWP inthe frequency domain. Note that although the illustrated CORESET iscontiguous in the frequency domain, it need not be. In addition, theCORESET may span less than three symbols in the time domain.

The DCI within the PDCCH carries information about uplink resourceallocation (persistent and non-persistent) and descriptions aboutdownlink data transmitted to the UE, referred to as uplink and downlinkgrants, respectively. More specifically, the DCI indicates the resourcesscheduled for the downlink data channel (e.g., PDSCH) and the uplinkdata channel (e.g., PUSCH). Multiple (e.g., up to eight) DCIs can beconfigured in the PDCCH, and these DCIs can have one of multipleformats. For example, there are different DCI formats for uplinkscheduling, for downlink scheduling, for uplink transmit power control(TPC), etc. A PDCCH may be transported by 1, 2, 4, 8, or 16 CCEs inorder to accommodate different DCI payload sizes or coding rates.

As illustrated in FIG. 4C, some of the REs (labeled “R”) carry DMRS forchannel estimation at the receiver (e.g., a base station, another UE,etc.). A UE may additionally transmit SRS in, for example, the lastsymbol of a slot. The SRS may have a comb structure, and a UE maytransmit SRS on one of the combs. In the example of FIG. 4C, theillustrated SRS is comb-2 over one symbol. The SRS may be used by a basestation to obtain the channel state information (CSI) for each UE. CSIdescribes how an RF signal propagates from the UE to the base stationand represents the combined effect of scattering, fading, and powerdecay with distance. The system uses the SRS for resource scheduling,link adaptation, massive MIMO, beam management, etc.

Currently, an SRS resource may span 1, 2, 4, 8, or 12 consecutivesymbols within a slot with a comb size of comb-2, comb-4, or comb-8. Thefollowing are the frequency offsets from symbol to symbol for the SRScomb patterns that are currently supported. 1-symbol comb-2: {0};2-symbol comb-2: {0, 1}; 4-symbol comb-2: {0, 1, 0, 1}; 4-symbol comb-4:{0, 2, 1, 3}; 8-symbol comb-4: {0, 2, 1, 3, 0, 2, 1, 3}; 12-symbolcomb-4: {0, 2, 1, 3, 0, 2, 1, 3, 0, 2, 1, 3}; 4-symbol comb-8: {0, 4, 2,6}; 8-symbol comb-8: {0, 4, 2, 6, 1, 5, 3, 7}; and 12-symbol comb-8: {0,4, 2, 6, 1, 5, 3, 7, 0, 4, 2, 6}.

A collection of resource elements that are used for transmission of SRSis referred to as an “SRS resource,” and may be identified by theparameter “SRS-ResourceId.” “The collection of resource elements canspan multiple PRBs in the frequency domain and N (e.g., one or more)consecutive symbol(s) within a slot in the time domain. In a given OFDMsymbol, an SRS resource occupies consecutive PRBs. An “SRS resource set”is a set of SRS resources used for the transmission of SRS signals, andis identified by an SRS resource set ID (“SRS-ResourceSetId”).

Generally, a UE transmits SRS to enable the receiving base station(either the serving base station or a neighboring base station) tomeasure the channel quality between the UE and the base station.However, SRS can also be specifically configured as uplink positioningreference signals for uplink-based positioning procedures, such asuplink time difference of arrival (UL-TDOA), round-trip-time (RTT),uplink angle-of-arrival (UL-AoA), etc. As used herein, the term “SRS”may refer to SRS configured for channel quality measurements or SRSconfigured for positioning purposes. The former may be referred toherein as “SRS-for-communication” and/or the latter may be referred toas “SRS-for-positioning” when needed to distinguish the two types ofSRS.

Several enhancements over the previous definition of SRS have beenproposed for SRS-for-positioning (also referred to as “UL-PRS”), such asa new staggered pattern within an SRS resource (except forsingle-symbol/comb-2), a new comb type for SRS, new sequences for SRS, ahigher number of SRS resource sets per component carrier, and a highernumber of SRS resources per component carrier. In addition, theparameters “SpatialRelationInfo” and “PathLossReference” are to beconfigured based on a downlink reference signal or SSB from aneighboring TRP. Further still, one SRS resource may be transmittedoutside the active BWP, and one SRS resource may span across multiplecomponent carriers. Also, SRS may be configured in RRC connected stateand only transmitted within an active BWP. Further, there may be nofrequency hopping, no repetition factor, a single antenna port, and newlengths for SRS (e.g., 8 and 12 symbols). There also may be open-looppower control and not closed-loop power control, and comb-8 (i.e., anSRS transmitted every eighth subcarrier in the same symbol) may be used.Lastly, the UE may transmit through the same transmit beam from multipleSRS resources for UL-AoA. All of these are features that are additionalto the current SRS framework, which is configured through RRC higherlayer signaling (and potentially triggered or activated through MACcontrol element (CE) or DCI).

FIG. 4D illustrates an example of various channels within an uplink slotof a frame, according to aspects of the disclosure. A random-accesschannel (RACH), also referred to as a physical random-access channel(PRACH), may be within one or more slots within a frame based on thePRACH configuration. The PRACH may include six consecutive RB pairswithin a slot. The PRACH allows the UE to perform initial system accessand achieve uplink synchronization. A physical uplink control channel(PUCCH) may be located on edges of the uplink system bandwidth. ThePUCCH carries uplink control information (UCI), such as schedulingrequests, CSI reports, a channel quality indicator (CQI), a precodingmatrix indicator (PMI), a rank indicator (RI), and HARQ ACK/NACKfeedback. The physical uplink shared channel (PUSCH) carries data, andmay additionally be used to carry a buffer status report (BSR), a powerheadroom report (PHR), and/or UCI.

Note that the terms “positioning reference signal” and “PRS” generallyrefer to specific reference signals that are used for positioning in NRand LTE systems. However, as used herein, the terms “positioningreference signal” and “PRS” may also refer to any type of referencesignal that can be used for positioning, such as but not limited to, PRSas defined in LTE and NR, TRS, PTRS, CRS, CSI-RS, DMRS, PSS, SSS, SSB,SRS, UL-PRS, etc. In addition, the terms “positioning reference signal”and “PRS” may refer to downlink or uplink positioning reference signals,unless otherwise indicated by the context. If needed to furtherdistinguish the type of PRS, a downlink positioning reference signal maybe referred to as a “DL-PRS,” and an uplink positioning reference signal(e.g., an SRS-for-positioning, PTRS) may be referred to as an “UL-PRS.”In addition, for signals that may be transmitted in both the uplink anddownlink (e.g., DMRS, PTRS), the signals may be prepended with “UL” or“DL” to distinguish the direction. For example, “UL-DMRS” may bedifferentiated from “DL-DMRS.”

NR supports a number of cellular network-based positioning technologies,including downlink-based, uplink-based, and downlink-and-uplink-basedpositioning methods. Downlink-based positioning methods include observedtime difference of arrival (OTDOA) in LTE, downlink time difference ofarrival (DL-TDOA) in NR, and downlink angle-of-departure (DL-AoD) in NR.In an OTDOA or DL-TDOA positioning procedure, a UE measures thedifferences between the times of arrival (ToAs) of reference signals(e.g., positioning reference signals (PRS)) received from pairs of basestations, referred to as reference signal time difference (RSTD) or timedifference of arrival (TDOA) measurements, and reports them to apositioning entity. More specifically, the UE receives the identifiers(IDs) of a reference base station (e.g., a serving base station) andmultiple non-reference base stations in assistance data. The UE thenmeasures the RSTD between the reference base station and each of thenon-reference base stations. Based on the known locations of theinvolved base stations and the RSTD measurements, the positioning entitycan estimate the UE's location.

For DL-AoD positioning, the positioning entity uses a beam report fromthe UE of received signal strength measurements of multiple downlinktransmit beams to determine the angle(s) between the UE and thetransmitting base station(s). The positioning entity can then estimatethe location of the UE based on the determined angle(s) and the knownlocation(s) of the transmitting base station(s).

Uplink-based positioning methods include uplink time difference ofarrival (UL-TDOA) and uplink angle-of-arrival (UL-AoA). UL-TDOA issimilar to DL-TDOA, but is based on uplink reference signals (e.g.,sounding reference signals (SRS)) transmitted by the UE. For UL-AoApositioning, one or more base stations measure the received signalstrength of one or more uplink reference signals (e.g., SRS) receivedfrom a UE on one or more uplink receive beams. The positioning entityuses the signal strength measurements and the angle(s) of the receivebeam(s) to determine the angle(s) between the UE and the basestation(s). Based on the determined angle(s) and the known location(s)of the base station(s), the positioning entity can then estimate thelocation of the UE.

Downlink-and-uplink-based positioning methods include enhanced cell-ID(E-CID) positioning and multi-round-trip-time (RTT) positioning (alsoreferred to as “multi-cell RTT”). In an RTT procedure, an initiator (abase station or a UE) transmits an RTT measurement signal (e.g., a PRSor SRS) to a responder (a UE or base station), which transmits an RTTresponse signal (e.g., an SRS or PRS) back to the initiator. The RTTresponse signal includes the difference between the ToA of the RTTmeasurement signal and the transmission time of the RTT response signal,referred to as the reception-to-transmission (Rx-Tx) time difference.The initiator calculates the difference between the transmission time ofthe RTT measurement signal and the ToA of the RTT response signal,referred to as the transmission-to-reception (Tx-Rx) time difference.The propagation time (also referred to as the “time of flight”) betweenthe initiator and the responder can be calculated from the Tx-Rx andRx-Tx time differences. Based on the propagation time and the knownspeed of light, the distance between the initiator and the responder canbe determined. For multi-RTT positioning, a UE performs an RTT procedurewith multiple base stations to enable its location to be determined(e.g., using multilateration) based on the known locations of the basestations. RTT and multi-RTT methods can be combined with otherpositioning techniques, such as UL-AoA and DL-AoD, to improve locationaccuracy.

The E-CID positioning method is based on radio resource management (RRM)measurements. In E-CID, the UE reports the serving cell ID, the timingadvance (TA), and the identifiers, estimated timing, and signal strengthof detected neighbor base stations. The location of the UE is thenestimated based on this information and the known locations of the basestation(s).

To assist positioning operations, a location server (e.g., locationserver 230, LMF 270, SLP 272) may provide assistance data to the UE. Forexample, the assistance data may include identifiers of the basestations (or the cells/TRPs of the base stations) from which to measurereference signals, the reference signal configuration parameters (e.g.,the number of consecutive positioning subframes, periodicity ofpositioning subframes, muting sequence, frequency hopping sequence,reference signal identifier, reference signal bandwidth, etc.), and/orother parameters applicable to the particular positioning method.Alternatively, the assistance data may originate directly from the basestations themselves (e.g., in periodically broadcasted overheadmessages, etc.). in some cases, the UE may be able to detect neighbornetwork nodes itself without the use of assistance data.

In the case of an OTDOA or DL-TDOA positioning procedure, the assistancedata may further include an expected RSTD value and an associateduncertainty, or search window, around the expected RSTD. In some cases,the value range of the expected RSTD may be +/−500 microseconds (μs). Insome cases, when any of the resources used for the positioningmeasurement are in FR1, the value range for the uncertainty of theexpected RSTD may be +/−32 μs. In other cases, when all of the resourcesused for the positioning measurement(s) are in FR2, the value range forthe uncertainty of the expected RSTD may be +/−8 μs.

A location estimate may be referred to by other names, such as aposition estimate, location, position, position fix, fix, or the like. Alocation estimate may be geodetic and comprise coordinates (e.g.,latitude, longitude, and possibly altitude) or may be civic and comprisea street address, postal address, or some other verbal description of alocation. A location estimate may further be defined relative to someother known location or defined in absolute terms (e.g., using latitude,longitude, and possibly altitude). A location estimate may include anexpected error or uncertainty (e.g., by including an area or volumewithin which the location is expected to be included with some specifiedor default level of confidence).

Positioning measurements are currently reported through higher layersignaling, specifically, LTE positioning protocol (LPP) signaling and/orRRC signaling. Such reports are referred to as “measurement reports,”“positioning reports,” and the like. LPP is used point-to-point betweena location server (e.g., location server 230, LMF 270, SLP 272) and a UEin order to position the UE using location related measurements obtainedfrom one or more reference sources (e.g., satellites for GPSpositioning, base stations for DL-TDOA positioning, WLAN APs for WLANpositioning, etc.). However, to reduce latency, techniques for reportingpositioning state information (PSI) using lower layer (e.g., Layer 1(L1)/Layer 2 (L2)) signaling have been introduced in NR. A PSI report isa low-layer positioning report, and may include RAT-dependentmeasurements, that is, measurements based on NR reference signals (e.g.,DL-PRS, TRS, SSB, etc.), or RAT-independent measurements, that is,measurements or other information derived from reference sources otherthan NR reference sources (e.g., Bluetooth, barometric sensor, motionsensor, GPS, OTDOA based on LTE PHY signals, E-CID based on LTE PHYsignals, etc.).

FIG. 5 illustrates an example wireless network structure 500 showinghigh-layer architecture enhancements for low-latency positioning. Thewireless network structure 500 is a reference point representation ofvarious network entities, similar to the wireless network structure 250in FIG. 2B. Network entities in FIG. 5 that have the same referencenumbers as network entities in FIG. 2B correspond to the networkentities illustrated in, and described with reference to, FIG. 2B. Forbrevity, those network entities are not described again here. Inaddition to the network entities illustrated in FIG. 2B, the wirelessnetwork structure 500 also includes a gateway mobile location center(GMLC) 268 and an external client/application function (AF) 570. TheGMLC 268 is the first node an external client/AF 570 accesses in acellular (e.g., LTE, NR) network, and sends positioning requests to theAMF 264. Further, in the example of FIG. 5 , the NG-RAN 220 includes aserving (S) gNB 222 and multiple neighboring (N) gNBs 222, each of whichmay include a location management component (LMC) 274.

FIG. 5 illustrates the control plane path 510 between the externalclient/AF 570 and a UE 204, which is used to set-up a location sessionwith the UE 204. Specifically, the external client/AF 570 sends alocation request to the GMLC 268, which forwards the request to the AMF264. The AMF 264 sends the location request to the serving (S) gNB 222in the NG-RAN 220, which transmits the request to the UE 204 over theair interface between the serving gNB 222 and the UE 204 (referred to asthe “Uu” interface). More specifically, an LMC 274 at the serving gNB222 handles reception and transmission of the location request. Thelocation request may direct the UE 204 to perform particularmeasurements (e.g., RSTD measurements, Rx-Tx time differencemeasurements, etc.) or report a location estimate calculated by the UE204 (e.g., based on GPS, WLAN, etc.).

After performing the requested measurements or calculating the locationestimate, the UE 204 responds to the location request by sending one ormore low layer positioning reports (e.g., PSI reports) to the servinggNB 222 over L1/L2 path 520. More specifically, the UE 204 sends the lowlayer positioning report(s) to the LMC 274 over the L1/L2 path 520. TheUE 204 can send the low layer positioning report(s) via L1 in uplinkcontrol information (UCI) and/or via L2 in MAC control elements(MAC-CEs). The low layer positioning report(s) include the requestedmeasurements or the location estimate.

The LMC 274 packages the low layer positioning report(s) from the UE 204and transmits them to the external client/AF 570 over a user plane path530. Specifically, the LMC 274 sends the low layer positioning report(s)to the UPF 262, which forwards the report(s) to the external client/AF570. Because of having an LMC 274 at the gNB 222, there is no need tosend the low layer positioning report(s) to the external client/AF 570via the LMF 270.

As noted above, measurement reports (also referred to as “positioningreports”) are currently reported via LPP signalling (Layer 3). There aredifferent information elements (IEs) in LPP that can be used to reporteach of the three RAT-dependent positioning methods currently supported(i.e., DL-TDOA, DL-AoD, multi-RTT). Specifically, TDOA measurements(i.e., RSTD measurements) are reported in an“NR-DL-TDOA-SignalMeasurementInformation” IE, DL-AoD measurements arereported in an “NR-DL-AoD-SignalMeasurementInformation” IE, andmulti-RTT measurements (e.g., UE Rx-Tx time difference measurements) arereported in an “NR-Multi-RTT-SignalMeasurementInformation” IE.

To reduce latency, it would be beneficial to report the informationcontained in these IEs over low layer (L1/L2) signalling (e.g., PSIreports). However, because low layer containers (e.g., UCI and MAC-CEcontainers) cannot carry as much information as higher layer reports(e.g., LPP IEs), techniques are needed to reduce the overhead of lowlayer reporting. As such, determining the typical size of these higherlayer measurement reports would be beneficial.

FIGS. 6A to 6C illustrate various LPP IEs that a UE can use to reportDL-TDOA measurements to the location server (e.g., location server 230,LMF 270, SLP 272). Specifically, FIG. 6A illustrates an“NR-DL-TDOA-SignalMeasurementInformation” IE 600 and an“NR-DL-TDOA-MeasElement” IE 620. FIG. 6B illustrates an“NR-DL-TDOA-AdditionalMeasurementElement” IE 640, which is used toreport additional DL-TDOA measurements that do not fit in the“NR-DL-TDOA-SignalMeasurementInformation” IE 600. FIG. 6C illustrates an“NR-TimeStamp” IE 660 and an “NR-TimingMeasQuality” IE 680. The“NR-TimeStamp” IE 660 is used to report the timestamps of the DL-TDOAmeasurements reported in an “NR-DL-TDOA-SignalMeasurementInformation” IE600 and any “NR-DL-TDOA-AdditionalMeasurementElement” IEs 620.

Table 1 below illustrates various fields in a DL-TDOA measurement reportand their usages and sizes.

TABLE 1 Op- tion- Field Usage Length (bits) al DL-PRS- ReferenceTRP/Resource/Set <=8 + 64 × 6 = Yes IdInfo-r16 for the RSTD (may bepicked 392 by the UE) Quality Quality of the reference ToA 7 No metricof reference ToA TRP-ID-r16 PRS ID of the TRP of the 8 No target cellnr-DL-PRS- PRS resource set of the target 6 Yes ResourceId-r16 cellNR-DL-PRS- Resource of the target cell 3 Yes ResourceSetId- r16nr-RSTD-r16 RSTD value [16-22] for k = No −1, 0, . . . , 5, where stepsize is T = T_(c)2^(k), T_(c) = 0.5 nsec nr-TimeStamp- Timestamp <=17:10 for SFN No r16 plus {4, 5, 6, 7 } bits for different SCS Qualitymetric Quality metric 7 No for RSTD

As shown in Table 1, there may be from 45 to 63 bits for each RSTDmeasurement, plus another seven bits for the quality metric for thereference ToA (i.e., the ToA of the reference signal from the referenceTRP). There may be up to 64 RSTD measurements per positioning frequencylayer because there may be up to 64 TRPs per positioning frequencylayer. If the UE chooses a different reference ToA, another eight to 392bits are needed to identify the new reference TRP. For example,reporting 10 RSTDs with an indication of just the TRP for each RSTDmeasurement, with a step size of 1 nanosecond (ns) and 30 kHz SCS,without changing the reference TRP, would require 497 bits (i.e.,49×10+7=497). If the UE were to choose a new reference TRP, there wouldbe an additional overhead of at least eight more bits.

FIG. 7 illustrates an example“NR-Multi-RTT-SignalMeasurementInformation” IE 700 that a UE can use toreport multi-RTT measurements to the location server (e.g., locationserver 230, LMF 270, SLP 272). The measurements are provided as a listof TRPs, where the first TRP in the list is used as the reference TRP.

Table 2 below illustrates various fields in a multi-RTT measurementreport and their usages and sizes.

TABLE 2 Op- tion- Field Usage Length (bits) al TRP-ID-r16 PRS ID of theTRP of the 8 No target cell nr-DL-PRS- PRS resource set of the 6 YesResourceId-r16 Target cell NR-DL-PRS- Resource of the target cell 3 YesResourceSetId-r16 nr-UE- Rx-Tx value [16-22] for k = No RxTxTimeDiff-−1, 0, . . . , 5, r16 where step size is T =T_(c)2^(k), T_(c) = 0.5 nsecnr-TimeStamp-r16 Timestamp <=17: 10 for SFN No plus {4, 5, 6, 7} bitsfor different SCS Quality Metric for Quality metric 7 No Rx-Tx

As shown in Table 2, there may be from 45 to 63 bits for each Rx-Tx timedifference measurement. As with RSTD measurements, there may be up to 64Rx-Tx time difference measurements per positioning frequency layerbecause there may be up to 64 TRPs per positioning frequency layer. Forexample, reporting 10 Rx-Tx time difference measurements with anindication of just the TRP for each RTT measurement, with a step size of1 ns and 30 kHz SCS, without changing the reference from the UE, wouldrequire 490 bits (49×10=490). Each 49 bits consists of eight bits forthe TRP ID, 19 bits for the RTT measurement, 15 bits for the timestamp,and seven bits for the quality metric.

As can be seen from the above examples, 30% of the 49 bits needed toreport TDOA or multi-RTT measurements is the timestamp. As such, toreduce the overhead of measurement reporting in order to reportpositioning measurements over low layer signaling (e.g., L1, L2), itwould be beneficial to reduce the number of bits needed for thetimestamp.

For low layer reporting, there is a fixed or known timeline forreporting the PSI reports, and there is no ambiguity on which are theassociated PRS that the UE used to derive the measurements and reportthem. As such, timestamp reporting for positioning measurements can bedefined with respect to a fixed reference point. That is, rather thanreport timestamps as absolute values, requiring up to 17 bits (seeTables 1 and 2) per timestamp, a timestamp can be reported as thedifference between the time a positioning measurement is taken/performedand the reference point. Such a timestamp may therefore indicate theamount of time relative to (e.g., before or after) the reference pointthat the positioning measurement is valid. Such a timestamp is referredto herein as a “differential timestamp” or a “relative timestamp,” orsimply a “timestamp” where it is clear from the context that thereferenced timestamp is a differential/relative timestamp. Reportingtimestamps in this way can significantly reduce the length (in bits) ofthe timestamp associated with a positioning measurement, and thereby,reduce the overhead of transmitting the timestamps in PSI reports.

As a first option, the reported differential timestamps may be relativeto the first or last slot of a first or last PRS instance of apositioning frequency layer. That is, each reported timestamp would bethe amount of time between the first or last slot of the first or lastPRS instance of a positioning frequency layer and the time the UEperformed the associated positioning measurement. For example, thereference point may be 3 ms after the last slot carrying the PRSresources of a PRS instance. When the serving base station receives theMAC-CE package containing the measurement report, there is exactknowledge of when the report was transmitted, and therefore, exactknowledge of which PRS were measured.

Still referring to the first option, if the PRS resources of a PRSinstance span over some number ‘X’ milliseconds, the reported timestampsmay be relative to the start of the PRS instance. Thus, for example, forX=20 ms in FR1 with 30 kHz, it would only take log 2(40)=6 bits toreport a differential timestamp. As another example, for X=40 ms in FR2with 120 kHz, it would only take log 2(40*8)=9 bits to report adifferential timestamp. For uplink reference signals, if the SRSresources of an SRS instance span over ‘X’ milliseconds, the timestampsmay be reported relative to the start of the SRS instance.

As a second option, the reference point for a timestamp may beconfigured by the network (e.g., the serving base station). In thiscase, the UE receives signaling that provides the reference point forthe timestamps for the next positioning report (e.g., PSI report). Forexample, the UE may receive a downlink MAC-CE command that containswhich point in time should be the reference point for calculatingdifferential timestamps, and the duration, or bit-width (i.e., size inbits), of the timestamps. As another example, the UE may receive DCIthat schedules the positioning report, or DCI that schedules the PRSresources to be reported.

As a third option, the UE may report a common reference point for allmeasurements in a positioning report, and then provide a differentialtimestamp for each measurement with respect to that reference point. Thecommon reference point may be reported by the UE via higher layersignaling (e.g., LPP), or may be reported in a low layer report at alower duty cycle than a positioning report. For example, if differentialtimestamps are being reported in L1 (e.g., in UCI), the common referencepoint may be reported in L2 (e.g., in a MAC-CE package).

In an aspect, a UE may indicate that the timestamps for the last ‘Y’ PRSinstances are being reported relative to a reference point. For example,a UE may report relative timestamps for PRS measurements from the lasttwo PRS instances (i.e., Y=2), whereas another UE may report relativetimestamps for PRS measurements from a single PRS instance (i.e., Y=1).

In an aspect, a UE may only be able to report relative timestamps forthe slots inside which a PRS or an SRS resource is configured. Thus, tocover a time domain of one second, for example, where PRS are configuredin only a region of 100 ms within that one second, then a timestampwould only need to be able to uniquely identify points inside the 100 mswithin the one second period. That is, the reference point would be theone second boundary, and a timestamp would need to have enough bits torepresent a point in time within 100 ms relative to the one secondboundary. This example is illustrated in FIG. 8 . Specifically, FIG. 8illustrates a timeline 800 in which PRS are transmitted inside 25 ms“chunks” (which may be one or more consecutive PRS instances, one ormore consecutive slots in which PRS are transmitted, or the like) withinsome length of time, such as one second. The reported timestamps wouldneed to be able to index only inside the PRS instances or slots or thelike in which the PRS are scheduled.

In an aspect, a UE may report a common reference point for thetimestamps for all measurements across multiple types of positioningmethods (e.g., DL-TDOA, multi-RTT, DL-AoD). A UE may also report thesame differential timestamps for different measurement types, therebyeliminating the need to report a differential timestamp for eachmeasurement. For example, if a UE has been configured to report RSTD,Rx-Tx time difference, and RSRP measurements, the UE will likely performthese measurements on the same PRS resources. As such, the timestampassociated with each type of measurement will be the same, or veryclose. If they are the same, the UE may report only one timestamp pergroup of positioning measurements (e.g., RSTD, Rx-Tx time difference,and RSRP measurements) taken of the same PRS resource. If the timestampsare different, the UE can report one timestamp for the group ofpositioning measurements relative to the reference point, and theremaining timestamps for the group of positioning measurements as thedifferences between the reference timestamp and the times at which theremaining positioning measurements were performed.

In an aspect, when a UE reports additional measurements (e.g.,additional RSTD, RSRP, or Rx-Tx time difference measurements), as wouldotherwise be reported in an “NR-DL-TDOA-AdditionalMeasurementElement” IE640, the same differential timestamp can be applied to all of theadditional measurements, or the additional measurements may beassociated with a differential timestamp report to reduce the overhead.In the latter case, similar to the above, the UE would report onedifferential timestamp for one of the additional positioning measurementas a reference timestamp, and report each remaining timestamp as theamount of the difference between the reference timestamp and the time atwhich the respective additional positioning measurement was performed.

In an aspect, a UE may determine a relative timestamp but not report it.The reason the UE may not need to report the timestamp is that both thebase station and the UE know when the PRS is/are scheduled, and theyalso know the exact time a PSI report is received at the base stationwhen the report is transmitted at low layers. Thus, the timestamp couldbe determined by the base station based on specified rules. For example,the timestamp may correspond to the earliest/latest/middle slot/frame ofthe latest PRS instance, or to the span of the latest PRS instance, orsome other similar rule.

As will be appreciated, by determining (and optionally reporting)timestamps relative to a reference point, that is, as the amount of timebetween the reference point and the time the associated positioningmeasurement was performed, rather than as an absolute value, fewer bitsare needed to report a timestamp, thereby reducing signaling overhead.In addition, as described above with reference to FIG. 5 , the low layerreports including the positioning measurements and time stamps may bereported to the serving base station (or LMC).

FIG. 9 illustrates an example method 900 of wireless communication,according to aspects of the disclosure. In an aspect, method 900 may beperformed by a UE (e.g., any of the UEs described herein).

At 910, the UE performs at least one positioning measurement of at leastone DL-PRS received from a TRP during a positioning session. In anaspect, operation 910 may be performed by the one or more WWANtransceivers 310, the one or more processors 332, memory 340, and/orpositioning component 342, any or all of which may be considered meansfor performing this operation.

At 920, the UE reports, to a positioning entity (e.g., location server230, LMF 270, SLP 272, LMC 226, external client 570, the serving basestation (with or without an LMC 226), etc.), a value of the at least onepositioning measurement via low layer signaling. In an aspect, operation920 may be performed by the one or more WWAN transceivers 310, the oneor more processors 332, memory 340, and/or positioning component 342,any or all of which may be considered means for performing thisoperation.

At 930, the UE determines (and optionally reports, to the positioningentity via the low layer signaling) a timestamp for the at least onepositioning measurement relative to a reference point, wherein thetimestamp comprises an amount of time between the reference point and atime at which the at least one positioning measurement is valid. In anaspect, operation 930 may be performed by the one or more WWANtransceivers 310, the one or more processors 332, memory 340, and/orpositioning component 342, any or all of which may be considered meansfor performing this operation.

FIG. 10 illustrates an example method 1000 of wireless communication,according to aspects of the disclosure. In an aspect, method 1000 may beperformed by a network entity (e.g., any of the base stations describedherein, an LMC, or the like).

At 1010, the network entity receives, from a UE (e.g., any of the UEsdescribed herein) via low layer signaling, a value of at least onepositioning measurement of at least one DL-PRS, the value of the atleast one positioning measurement received at a reception time during apositioning session between the network entity and the UE. In an aspect,operation 1010 may be performed by the one or more WWAN transceivers350, the one or more processors 384, memory 386, and/or positioningcomponent 388, any or all of which may be considered means forperforming this operation.

At 1020, the network entity determines a reference point for a timestampfor the at least one positioning measurement. In an aspect, operation1020 may be performed by the one or more WWAN transceivers 350, the oneor more processors 384, memory 386, and/or positioning component 388,any or all of which may be considered means for performing thisoperation.

At 1030, the network entity determines the timestamp based on thereception time, the reference point, and an offset, wherein thetimestamp comprises an amount of time relative to the reference pointthat the at least one positioning measurement is valid. In an aspect,operation 1030 may be performed by the one or more WWAN transceivers350, the one or more processors 384, memory 386, and/or positioningcomponent 388, any or all of which may be considered means forperforming this operation.

As will be appreciated, a technical advantage of the methods 900 and1000 is reduced signaling overhead for lower layer positioningmeasurement reporting.

In the detailed description above it can be seen that different featuresare grouped together in examples. This manner of disclosure should notbe understood as an intention that the example clauses have morefeatures than are explicitly mentioned in each clause. Rather, thevarious aspects of the disclosure may include fewer than all features ofan individual example clause disclosed. Therefore, the following clausesshould hereby be deemed to be incorporated in the description, whereineach clause by itself can stand as a separate example. Although eachdependent clause can refer in the clauses to a specific combination withone of the other clauses, the aspect(s) of that dependent clause are notlimited to the specific combination. It will be appreciated that otherexample clauses can also include a combination of the dependent clauseaspect(s) with the subject matter of any other dependent clause orindependent clause or a combination of any feature with other dependentand independent clauses. The various aspects disclosed herein expresslyinclude these combinations, unless it is explicitly expressed or can bereadily inferred that a specific combination is not intended (e.g.,contradictory aspects, such as defining an element as both an insulatorand a conductor). Furthermore, it is also intended that aspects of aclause can be included in any other independent clause, even if theclause is not directly dependent on the independent clause.

Implementation examples are described in the following numbered clauses:

Clause 1. A method of wireless communication performed by a userequipment (UE), comprising: performing at least one positioningmeasurement of at least one downlink positioning reference signal(DL-PRS) received from a transmission-reception point (TRP) during apositioning session; reporting, to a positioning entity, a value of theat least one positioning measurement via low layer signaling; anddetermining a timestamp for the at least one positioning measurementrelative to a reference point, wherein the timestamp comprises an amountof time relative to the reference point that the at least onepositioning measurement is valid.

Clause 2. The method of clause 1, wherein the reference point isrelative to a symbol, a slot boundary, a subframe boundary, or a frameboundary.

Clause 3. The method of any of clauses 1 to 2, wherein the referencepoint is a period of time after a last slot of a last DL-PRS instancecontaining the at least one DL-PRS.

Clause 4. The method of any of clauses 1 to 3, wherein the referencepoint is a start of a DL-PRS instance containing the at least oneDL-PRS.

Clause 5. The method of clause 4, wherein the reference point is thestart of the DL-PRS instance containing the at least one DL-PRS based onDL-PRS resources of the DL-PRS instance spanning more than a thresholdperiod of time.

Clause 6. The method of any of clauses 1 to 5, further comprising:receiving the reference point and a size of the timestamp from the TRPvia second low layer signaling.

Clause 7. The method of clause 6, wherein the second low layer signalingcomprises a medium access control control element (MAC-CE) command ordownlink control information (DCI).

Clause 8. The method of any of clauses 1 to 7, wherein the at least onepositioning measurement comprises a plurality of positioningmeasurements.

Clause 9. The method of clause 8, further comprising: determining atimestamp for each of the plurality of positioning measurements relativeto the reference point, wherein each timestamp comprises an amount oftime between the reference point and a time at which a correspondingpositioning measurement of the plurality of positioning measurements isvalid.

Clause 10. The method of any of clauses 8 to 9, wherein the plurality ofpositioning measurements comprises positioning measurements for aplurality of different positioning methods being performed by the UEduring the positioning session.

Clause 11. The method of clause 10, wherein the reference point appliesto all of the positioning measurements for the plurality of differentpositioning methods.

Clause 12. The method of any of clauses 10 to 11, wherein the UEdetermines only one timestamp per group of positioning measurementsperformed on the same DL-PRS.

Clause 13. The method of any of clauses 10 to 12, further comprising:reporting an additional plurality of positioning measurements associatedwith the plurality of different positioning methods; and determiningtimestamps for the additional plurality of positioning measurementsrelative to the reference point.

Clause 14. The method of any of clauses 1 to 13, further comprising:reporting the reference point to the TRP or the positioning entity.

Clause 15. The method of clause 14, wherein: the reference point isreported via higher layer signaling, or the reference point is reportedvia low layer signaling with a longer duty cycle than the value of theat least one positioning measurement.

Clause 16. The method of any of clauses 1 to 15, wherein the referencepoint applies to a threshold number of most recent DL-PRS instances.

Clause 17. The method of any of clauses 1 to 16, wherein the timestampcomprises enough bits to specify a time of the at least one positioningmeasurement within a subset of slots within a given period of timeduring which DL-PRS are scheduled.

Clause 18. The method of any of clauses 1 to 17, wherein the referencepoint comprises a timestamp of another measurement of another DL-PRSperformed by the UE during the positioning session.

Clause 19. The method of any of clauses 1 to 18, further comprising:reporting, to the positioning entity via the low layer signaling, thetimestamp for the at least one positioning measurement relative to thereference point.

Clause 20. The method of any of clauses 1 to 19, wherein the low layersignaling comprises uplink control information (UCI) or MAC-CEsignaling.

Clause 21. The method of any of clauses 1 to 20, wherein: thepositioning entity comprises a base station associated with the TRP or alocation management component (LMC) associated with the TRP, and the TRPis a serving TRP.

Clause 22. A method of wireless communication performed by a networkentity, comprising: receiving, from a user equipment (UE) via low layersignaling, a value of at least one positioning measurement of at leastone downlink positioning reference signal (DL-PRS), the value of the atleast one positioning measurement received at a reception time during apositioning session between the network entity and the UE; determining areference point for a timestamp for the at least one positioningmeasurement; and determining the timestamp based on the reception time,the reference point, and an offset, wherein the timestamp comprises anamount of time relative to the reference point that the at least onepositioning measurement is valid.

Clause 23. The method of clause 22, wherein the reference point isrelative to a symbol, a slot boundary, a subframe boundary, or a frameboundary.

Clause 24. The method of any of clauses 22 to 23, wherein the referencepoint is a period of time after a last slot of a last DL-PRS instancecontaining the at least one DL-PRS.

Clause 25. The method of any of clauses 22 to 24, wherein the referencepoint is a start of a DL-PRS instance containing the at least oneDL-PRS.

Clause 26. The method of clause 25, wherein the reference point is thestart of the DL-PRS instance containing the at least one DL-PRS based onDL-PRS resources of the DL-PRS instance spanning more than a thresholdperiod of time.

Clause 27. The method of any of clauses 22 to 26, wherein determiningthe reference point comprises: receiving the reference point from theUE.

Clause 28. The method of clause 27, wherein: the reference point isreceived via higher layer signaling, or the reference point is receivedvia low layer signaling with a longer duty cycle than the value of theat least one positioning measurement.

Clause 29. The method of any of clauses 22 to 28, wherein the referencepoint applies to a threshold number of most recent DL-PRS instances.

Clause 30. The method of any of clauses 22 to 29, wherein the timestampcomprises enough bits to specify a time of the at least one positioningmeasurement within a subset of slots within a given period of timeduring which DL-PRS are scheduled.

Clause 31. The method of any of clauses 22 to 30, wherein the referencepoint comprises a timestamp of another measurement of another DL-PRSperformed by the UE during the positioning session.

Clause 32. The method of any of clauses 22 to 31, wherein the offsetcomprises a length of time between a time at which the UE measures theat least one DL-PRS and a time at which the UE transmits the value ofthe at least one positioning measurement.

Clause 33. The method of any of clauses 22 to 32, wherein the low layersignaling comprises uplink control information (UCI) or MAC-CEsignaling.

Clause 34. The method of any of clauses 1 to 33, wherein the networkentity comprises: a base station serving the UE, or a locationmanagement component (LMC).

Clause 35. An apparatus comprising a memory, at least one transceiver,and at least one processor communicatively coupled to the memory and theat least one transceiver, the memory, the at least one transceiver, andthe at least one processor configured to perform a method according toany of clauses 1 to 34.

Clause 36. An apparatus comprising means for performing a methodaccording to any of clauses 1 to 34.

Clause 37. A non-transitory computer-readable medium storingcomputer-executable instructions, the computer-executable comprising atleast one instruction for causing a computer or processor to perform amethod according to any of clauses 1 to 34.

Those of skill in the art will appreciate that information and signalsmay be represented using any of a variety of different technologies andtechniques. For example, data, instructions, commands, information,signals, bits, symbols, and chips that may be referenced throughout theabove description may be represented by voltages, currents,electromagnetic waves, magnetic fields or particles, optical fields orparticles, or any combination thereof.

Further, those of skill in the art will appreciate that the variousillustrative logical blocks, modules, circuits, and algorithm stepsdescribed in connection with the aspects disclosed herein may beimplemented as electronic hardware, computer software, or combinationsof both. To clearly illustrate this interchangeability of hardware andsoftware, various illustrative components, blocks, modules, circuits,and steps have been described above generally in terms of theirfunctionality. Whether such functionality is implemented as hardware orsoftware depends upon the particular application and design constraintsimposed on the overall system. Skilled artisans may implement thedescribed functionality in varying ways for each particular application,but such implementation decisions should not be interpreted as causing adeparture from the scope of the present disclosure.

The various illustrative logical blocks, modules, and circuits describedin connection with the aspects disclosed herein may be implemented orperformed with a general purpose processor, a digital signal processor(DSP), an ASIC, a field-programmable gate array (FPGA), or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A general-purpose processor may be amicroprocessor, but in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices,for example, a combination of a DSP and a microprocessor, a plurality ofmicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration.

The methods, sequences and/or algorithms described in connection withthe aspects disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.A software module may reside in random access memory (RAM), flashmemory, read-only memory (ROM), erasable programmable ROM (EPROM),electrically erasable programmable ROM (EEPROM), registers, hard disk, aremovable disk, a CD-ROM, or any other form of storage medium known inthe art. An example storage medium is coupled to the processor such thatthe processor can read information from, and write information to, thestorage medium. In the alternative, the storage medium may be integralto the processor. The processor and the storage medium may reside in anASIC. The ASIC may reside in a user terminal (e.g., UE). In thealternative, the processor and the storage medium may reside as discretecomponents in a user terminal.

In one or more example aspects, the functions described may beimplemented in hardware, software, firmware, or any combination thereof.If implemented in software, the functions may be stored on ortransmitted over as one or more instructions or code on acomputer-readable medium. Computer-readable media includes both computerstorage media and communication media including any medium thatfacilitates transfer of a computer program from one place to another. Astorage media may be any available media that can be accessed by acomputer. By way of example, and not limitation, such computer-readablemedia can comprise RAM, ROM, EEPROM, CD-ROM or other optical diskstorage, magnetic disk storage or other magnetic storage devices, or anyother medium that can be used to carry or store desired program code inthe form of instructions or data structures and that can be accessed bya computer. Also, any connection is properly termed a computer-readablemedium. For example, if the software is transmitted from a website,server, or other remote source using a coaxial cable, fiber optic cable,twisted pair, digital subscriber line (DSL), or wireless technologiessuch as infrared, radio, and microwave, then the coaxial cable, fiberoptic cable, twisted pair, DSL, or wireless technologies such asinfrared, radio, and microwave are included in the definition of medium.Disk and disc, as used herein, includes compact disc (CD), laser disc,optical disc, digital versatile disc (DVD), floppy disk and Blu-ray discwhere disks usually reproduce data magnetically, while discs reproducedata optically with lasers. Combinations of the above should also beincluded within the scope of computer-readable media.

While the foregoing disclosure shows illustrative aspects of thedisclosure, it should be noted that various changes and modificationscould be made herein without departing from the scope of the disclosureas defined by the appended claims. The functions, steps and/or actionsof the method claims in accordance with the aspects of the disclosuredescribed herein need not be performed in any particular order.Furthermore, although elements of the disclosure may be described orclaimed in the singular, the plural is contemplated unless limitation tothe singular is explicitly stated.

What is claimed is:
 1. A method of wireless communication performed by auser equipment (UE), comprising: performing at least one positioningmeasurement of at least one downlink positioning reference signal(DL-PRS) received from a transmission-reception point (TRP) during apositioning session; reporting, to a positioning entity, a value of theat least one positioning measurement via low layer signaling; anddetermining a timestamp for the at least one positioning measurementrelative to a reference point, wherein the timestamp comprises an amountof time relative to the reference point that the at least onepositioning measurement is valid, and wherein the timestamp comprisesenough bits to specify a time of the at least one positioningmeasurement within a subset of slots within a given period of timeduring which DL-PRS are scheduled.
 2. The method of claim 1, wherein thereference point is relative to a symbol, a slot boundary, a subframeboundary, or a frame boundary.
 3. The method of claim 1, wherein thereference point is a period of time after a last slot of a last DL-PRSinstance containing the at least one DL-PRS.
 4. The method of claim 1,wherein the reference point is a start of a DL-PRS instance containingthe at least one DL-PRS.
 5. The method of claim 4, wherein the referencepoint is the start of the DL-PRS instance containing the at least oneDL-PRS based on DL-PRS resources of the DL-PRS instance spanning morethan a threshold period of time.
 6. The method of claim 1, furthercomprising: receiving the reference point and a size of the timestampfrom the TRP via second low layer signaling.
 7. The method of claim 6,wherein the second low layer signaling comprises a medium access controlcontrol element (MAC-CE) command or downlink control information (DCI).8. The method of claim 1, wherein the at least one positioningmeasurement comprises a plurality of positioning measurements.
 9. Themethod of claim 8, further comprising: determining a timestamp for eachof the plurality of positioning measurements relative to the referencepoint, wherein each timestamp comprises an amount of time between thereference point and a time at which a corresponding positioningmeasurement of the plurality of positioning measurements is valid. 10.The method of claim 8, wherein the plurality of positioning measurementscomprises positioning measurements for a plurality of differentpositioning methods being performed by the UE during the positioningsession.
 11. The method of claim 10, wherein the reference point appliesto all of the positioning measurements for the plurality of differentpositioning methods.
 12. The method of claim 10, wherein the UEdetermines only one timestamp per group of positioning measurementsperformed on the same DL-PRS.
 13. The method of claim 10, furthercomprising: reporting an additional plurality of positioningmeasurements associated with the plurality of different positioningmethods; and determining timestamps for the additional plurality ofpositioning measurements relative to the reference point.
 14. The methodof claim 1, further comprising: reporting the reference point to the TRPor the positioning entity.
 15. The method of claim 14, wherein: thereference point is reported via higher layer signaling, or the referencepoint is reported via low layer signaling with a longer duty cycle thanthe value of the at least one positioning measurement.
 16. The method ofclaim 1, wherein the reference point applies to a threshold number ofmost recent DL-PRS instances.
 17. The method of claim 1, wherein thereference point comprises a timestamp of another measurement of anotherDL-PRS performed by the UE during the positioning session.
 18. Themethod of claim 1, further comprising: reporting, to the positioningentity via the low layer signaling, the timestamp for the at least onepositioning measurement relative to the reference point.
 19. The methodof claim 1, wherein the low layer signaling comprises uplink controlinformation (UCI) or MAC-CE signaling.
 20. The method of claim 1,wherein: the positioning entity comprises a base station associated withthe TRP or a location management component (LMC) associated with theTRP, and the TRP is a serving TRP.
 21. A method of wirelesscommunication performed by a network entity, comprising: receiving, froma user equipment (UE) via low layer signaling, a value of at least onepositioning measurement of at least one downlink positioning referencesignal (DL-PRS), the value of the at least one positioning measurementreceived at a reception time during a positioning session between thenetwork entity and the UE; determining a reference point for a timestampfor the at least one positioning measurement; and determining thetimestamp based on the reception time, the reference point, and anoffset, wherein the timestamp comprises an amount of time relative tothe reference point that the at least one positioning measurement isvalid.
 22. The method of claim 21, wherein the reference point isrelative to a symbol, a slot boundary, a subframe boundary, or a frameboundary.
 23. The method of claim 21, wherein the reference point is aperiod of time after a last slot of a last DL-PRS instance containingthe at least one DL-PRS.
 24. The method of claim 21, wherein thereference point is a start of a DL-PRS instance containing the at leastone DL-PRS.
 25. The method of claim 24, wherein the reference point isthe start of the DL-PRS instance containing the at least one DL-PRSbased on DL-PRS resources of the DL-PRS instance spanning more than athreshold period of time.
 26. The method of claim 21, whereindetermining the reference point comprises: receiving the reference pointfrom the UE.
 27. The method of claim 26, wherein: the reference point isreceived via higher layer signaling, or the reference point is receivedvia low layer signaling with a longer duty cycle than the value of theat least one positioning measurement.
 28. The method of claim 21,wherein the reference point applies to a threshold number of most recentDL-PRS instances.
 29. The method of claim 21, wherein the timestampcomprises enough bits to specify a time of the at least one positioningmeasurement within a subset of slots within a given period of timeduring which DL-PRS are scheduled.
 30. The method of claim 21, whereinthe reference point comprises a timestamp of another measurement ofanother DL-PRS performed by the UE during the positioning session. 31.The method of claim 21, wherein the offset comprises a length of timebetween a time at which the UE measures the at least one DL-PRS and atime at which the UE transmits the value of the at least one positioningmeasurement.
 32. The method of claim 21, wherein the low layer signalingcomprises uplink control information (UCI) or MAC-CE signaling.
 33. Themethod of claim 21, wherein the network entity comprises: a base stationserving the UE, or a location management component (LMC).
 34. A userequipment (UE), comprising: a memory; at least one transceiver; and atleast one processor communicatively coupled to the memory and the atleast one transceiver, the at least one processor configured to: performat least one positioning measurement of at least one downlinkpositioning reference signal (DL-PRS) received from atransmission-reception point (TRP) during a positioning session; report,to a positioning entity, via the at least one transceiver, a value ofthe at least one positioning measurement via low layer signaling; anddetermine a timestamp for the at least one positioning measurementrelative to a reference point, wherein the timestamp comprises an amountof time relative to the reference point that the at least onepositioning measurement is valid, and wherein the timestamp comprisesenough bits to specify a time of the at least one positioningmeasurement within a subset of slots within a given period of timeduring which DL-PRS are scheduled.
 35. The UE of claim 34, wherein thereference point is relative to a symbol, a slot boundary, a subframeboundary, or a frame boundary.
 36. The UE of claim 34, wherein thereference point is a period of time after a last slot of a last DL-PRSinstance containing the at least one DL-PRS.
 37. The UE of claim 34,wherein the reference point is a start of a DL-PRS instance containingthe at least one DL-PRS.
 38. The UE of claim 37, wherein the referencepoint is the start of the DL-PRS instance containing the at least oneDL-PRS based on DL-PRS resources of the DL-PRS instance spanning morethan a threshold period of time.
 39. The UE of claim 34, wherein the atleast one processor is further configured to: receive, via the at leastone transceiver, the reference point and a size of the timestamp fromthe TRP via second low layer signaling.
 40. The UE of claim 39, whereinthe second low layer signaling comprises a medium access control controlelement (MAC-CE) command or downlink control information (DCI).
 41. TheUE of claim 34, wherein the at least one positioning measurementcomprises a plurality of positioning measurements.
 42. The UE of claim41, wherein the at least one processor is further configured to:determine a timestamp for each of the plurality of positioningmeasurements relative to the reference point, wherein each timestampcomprises an amount of time between the reference point and a time atwhich a corresponding positioning measurement of the plurality ofpositioning measurements is valid.
 43. The UE of claim 41, wherein theplurality of positioning measurements comprises positioning measurementsfor a plurality of different positioning methods being performed by theUE during the positioning session.
 44. The UE of claim 43, wherein thereference point applies to all of the positioning measurements for theplurality of different positioning methods.
 45. The UE of claim 43,wherein the UE determines only one timestamp per group of positioningmeasurements performed on the same DL-PRS.
 46. The UE of claim 43,wherein the at least one processor is further configured to: report anadditional plurality of positioning measurements associated with theplurality of different positioning methods; and determine timestamps forthe additional plurality of positioning measurements relative to thereference point.
 47. The UE of claim 34, wherein the at least oneprocessor is further configured to: report the reference point to theTRP or the positioning entity.
 48. The UE of claim 47, wherein: thereference point is reported via higher layer signaling, or the referencepoint is reported via low layer signaling with a longer duty cycle thanthe value of the at least one positioning measurement.
 49. The UE ofclaim 34, wherein the reference point applies to a threshold number ofmost recent DL-PRS instances.
 50. The UE of claim 34, wherein thereference point comprises a timestamp of another measurement of anotherDL-PRS performed by the UE during the positioning session.
 51. The UE ofclaim 34, wherein the at least one processor is further configured to:report, to the positioning entity via the low layer signaling, thetimestamp for the at least one positioning measurement relative to thereference point.
 52. The UE of claim 34, wherein the low layer signalingcomprises uplink control information (UCI) or MAC-CE signaling.
 53. TheUE of claim 34, wherein: the positioning entity comprises a base stationassociated with the TRP or a location management component (LMC)associated with the TRP, and the TRP is a serving TRP.
 54. The UE ofclaim 34, wherein the positioning entity comprises: a base stationserving the UE, or a location management component (LMC).
 55. A networkentity, comprising: a memory; at least one transceiver; and at least oneprocessor communicatively coupled to the memory and the at least onetransceiver, the at least one processor configured to: receive, via theat least one transceiver, from a user equipment (UE) via low layersignaling, a value of at least one positioning measurement of at leastone downlink positioning reference signal (DL-PRS), the value of the atleast one positioning measurement received at a reception time during apositioning session between the network entity and the UE; determine areference point for a timestamp for the at least one positioningmeasurement; and determine the timestamp based on the reception time,the reference point, and an offset, wherein the timestamp comprises anamount of time relative to the reference point that the at least onepositioning measurement is valid.
 56. The network entity of claim 55,wherein the reference point is relative to a symbol, a slot boundary, asubframe boundary, or a frame boundary.
 57. The network entity of claim55, wherein the reference point is a period of time after a last slot ofa last DL-PRS instance containing the at least one DL-PRS.
 58. Thenetwork entity of claim 55, wherein the reference point is a start of aDL-PRS instance containing the at least one DL-PRS.
 59. The networkentity of claim 58, wherein the reference point is the start of theDL-PRS instance containing the at least one DL-PRS based on DL-PRSresources of the DL-PRS instance spanning more than a threshold periodof time.
 60. The network entity of claim 55, wherein the at least oneprocessor being configured to determine the reference point comprisesthe at least one processor being configured to: receive, via the atleast one transceiver, the reference point from the UE.
 61. The networkentity of claim 60, wherein: the reference point is received via higherlayer signaling, or the reference point is received via low layersignaling with a longer duty cycle than the value of the at least onepositioning measurement.
 62. The network entity of claim 55, wherein thereference point applies to a threshold number of most recent DL-PRSinstances.
 63. The network entity of claim 55, wherein the timestampcomprises enough bits to specify a time of the at least one positioningmeasurement within a subset of slots within a given period of timeduring which DL-PRS are scheduled.
 64. The network entity of claim 55,wherein the reference point comprises a timestamp of another measurementof another DL-PRS performed by the UE during the positioning session.65. The network entity of claim 55, wherein the offset comprises alength of time between a time at which the UE measures the at least oneDL-PRS and a time at which the UE transmits the value of the at leastone positioning measurement.
 66. The network entity of claim 55, whereinthe low layer signaling comprises uplink control information (UCI) orMAC-CE signaling.
 67. A user equipment (UE), comprising: means forperforming at least one positioning measurement of at least one downlinkpositioning reference signal (DL-PRS) received from atransmission-reception point (TRP) during a positioning session; meansfor reporting, to a positioning entity, a value of the at least onepositioning measurement via low layer signaling; and means fordetermining a timestamp for the at least one positioning measurementrelative to a reference point, wherein the timestamp comprises an amountof time relative to the reference point that the at least onepositioning measurement is valid, and wherein the timestamp comprisesenough bits to specify a time of the at least one positioningmeasurement within a subset of slots within a given period of timeduring which DL-PRS are scheduled.
 68. A network entity, comprising:means for receiving, from a user equipment (UE) via low layer signaling,a value of at least one positioning measurement of at least one downlinkpositioning reference signal (DL-PRS), the value of the at least onepositioning measurement received at a reception time during apositioning session between the network entity and the UE; means fordetermining a reference point for a timestamp for the at least onepositioning measurement; and means for determining the timestamp basedon the reception time, the reference point, and an offset, wherein thetimestamp comprises an amount of time relative to the reference pointthat the at least one positioning measurement is valid.
 69. Anon-transitory computer-readable medium storing computer-executableinstructions that, when executed by a user equipment (UE), cause the UEto: perform at least one positioning measurement of at least onedownlink positioning reference signal (DL-PRS) received from atransmission-reception point (TRP) during a positioning session; report,to a positioning entity, a value of the at least one positioningmeasurement via low layer signaling; and determine a timestamp for theat least one positioning measurement relative to a reference point,wherein the timestamp comprises an amount of time relative to thereference point that the at least one positioning measurement is valid,and wherein the timestamp comprises enough bits to specify a time of theat least one positioning measurement within a subset of slots within agiven period of time during which DL-PRS are scheduled.
 70. Anon-transitory computer-readable medium storing computer-executableinstructions that, when executed by a network entity, cause the networkentity to: receive, from a user equipment (UE) via low layer signaling,a value of at least one positioning measurement of at least one downlinkpositioning reference signal (DL-PRS), the value of the at least onepositioning measurement received at a reception time during apositioning session between the network entity and the UE; determine areference point for a timestamp for the at least one positioningmeasurement; and determine the timestamp based on the reception time,the reference point, and an offset, wherein the timestamp comprises anamount of time relative to the reference point that the at least onepositioning measurement is valid.